I have written web standards several times for jobs in the past.  So many times that I wrote them for myself so I wouldn't have to keep writing them.  They probably aren't all that important for us, but you may find it a good read or something to share with a client that is interested in this sort of thing.  So much of SEO is related to your content after all...

Writing Standards For Web pages

The purpose of these standards is to improve the usability of pages (how easy are they to read) as well as the search-ability (how easy are they to find).

There is a lot of research on web writing styles available online.  The foremost authority on most things web is Jakob Nielsen.  A collection of articles for web writing standards can be found here:  http://www.useit.com/papers/webwriting/

Executive Summary
Inverted Pyramid
Put the most important information at the top of the page.

Be Concise
People read computer screens 25% slower than print.  Web pages should be half as long as their print equivalents.

Scan-able
Web users do not read, they scan.  Use headings and lists judiciously.  Highlight keywords.  Start headings and paragraphs with keywords.

Credibility
Web pages inherently lack credibility.  Write in an objective manner, quote experts, cite facts, and keep information up to date to increase trustworthiness.

Search-ability
If a user doesn’t know exactly where to go, he is going to search – most likely with google.  Modern search engines rank pages by the relevancy of their content and markers – such as titles, headings, and links within the content.

Grammar
Some web specific grammar rules to be referenced in conjunction with any corporate standards.

Lower Literacy Users
The internet is a global medium and not all visitors are native English speakers.  Lower literacy users have special needs and it turns out that what is good for them is good for higher-literacy users as well.

Inverted Pyramid
Overview – What is an Inverted Pyramid?
The inverted pyramid is a writing style that starts a page with the conclusion (the most important information) follows with key supporting information, and ends with specific details.  The reader immediately knows the key findings and purpose of the page and can stop reading at any time.

Web users are impatient and critical; using the inverted pyramid immediately informs them if they have arrived at the correct destination or whether they need to continue their search.

Title & Summary – The most important elements
The most important element on the page is the title.  The title needs to clearly state the page’s purpose and should contain the keywords that a user may have searched to find the page.

A summary needs to follow the title.  The summary should be short: two sentences maximum.  The user should confidently know what they can find on the rest of the page after reading the summary.  The summary will capture the interest of a user that has found what they are looking for; it is not intended to generate interest in a user that is looking for something else.

Scrolling & Scanning – Only interested users scroll
Users don't like to scroll and will read only the top of a page to judge their interest. Very interested readers will scroll, but they are more likely to scan than to read.

“Scanners” will read the first line (or less) of each paragraph, skipping the rest if it appears to be irrelevant. Information should be prioritized so the first sentence of each paragraph indicates what the paragraph will contain.  See “Scan-able” for more information.

Be Concise!
Overview – Get to the point
Keep sentences short and to the point.  People read computer screens 25% slower than print and tend to scan more than they read.  Web pages should be half as long as their print equivalents.

Stay Relevant – Don’t mix your messages
Avoid unnecessary content and stick to your message. Web users do not want to read “marketese” or welcome messages.

Using paragraphs – One idea per paragraph
Write short, tight paragraphs following these guidelines:

Short, direct sentences (20 to 25 words).
Break up long paragraphs (three to five sentences).
Be succinct. Use only your best details and examples.
Use simple sentence structures: Convoluted writing and complex words are difficult to understand online.

Page Length - Avoid long pages
Users don't like to scroll, so keep it short and to the point. BUT - do not break up information into separate pages if it belongs together: moving pages is more disruptive than scrolling

Lists – Great for scanning, but keep them short
Limit the number of items in a single list to no more than nine. Limit lists to no more than two levels: primary and secondary.

Scan-able
Overview – Web users don’t read
79% of users scan new pages, only 16% read word-by-word.  Users scan in an “F-Pattern” and will read the page title, the summary, and the first few words starting paragraphs and headings.

Increase usability with scan-able text such as:

meaningful headings
short and focused paragraphs
bulleted & numbered lists
hypertext links
block quotes
highlighted keywords
numbers

Structure & Headings – Scanner friendly formatting
Properly constructed headings organize a document and summarize the content found beneath them.  Headings should clearly describe what the following text is about even when read out of context.

Headings must be properly coded so that the topmost heading on the page is an H1, and subsequent headings (h2, h3, h4, etc) are organized structurally.  The hierarchy of headings should be no deeper than four levels. Lower-level heads are hard to distinguish and disorienting to online readers.

Headings should start with information carrying words (first 3 words) that users will notice when scanning the left side of the page.  It is ok to use passive voice when constructing a heading if it improves scan-ability.  Skip leading articles like "the" and "a" if the sentence still makes sense without them.

To ensure an adequate number of headings, try to create a heading for each “thought” or paragraph on a page.  Leave the heading in if it makes sense.

Heading Don’ts
Puns and clever headlines obscure content and are difficult to scan; use plain language.
Do not tease or try to entice users to click to find out what a page is about: users typically will not bother.
Paragraphs – Short and sweet
Large blocks of text are more difficult to read online than in print and should be broken up into short sentences and paragraphs.  Each paragraph should contain one main idea; use a second paragraph for a second idea.

Like headings, paragraphs should start with information carrying words (first 3 words) that users will notice when scanning the left side of the page. 

Lists – Full of important facts and points
Bulleted and numbered lists attract the scanning eye and draw attention to important points.  Use numbered lists when the order of entries is important and unnumbered lists when the sequence is not important.  Lists are preferable to lengthy comma separated sentences.

Limit the number of items in a single list to no more than nine. Limit lists to no more than two levels: primary and secondary.

Links – What scanners are looking for
Hyperlinks stand out by virtue of being colored and underlined (default state). Scanners will fix on hyperlink text, so they should contain keywords.  Links should contain keywords for SEO purposes as well.

Quotes – Add credibility and interest
Block quotes (those that are pulled out of the flow of the rest of the text) are very effective at attracting the scanner’s eyes.  A quote also lends credibility to a topic.

Bolding – Makes keywords stand out
Within paragraphs, use bold to make keywords or short statements stand out.  These elements help guide readers' eyes towards the most important content. 

Bold and italics can be used more in online than in print, but should still be used sparingly for maximum effect.  Bold is more noticeable and is preferable to italics.

Never underline or use blue to highlight words as those formats can be confused for being hyperlinks.
Highlight only information-carrying words. Avoid highlighting long phrases as a scanning eye can only pick up two (or at most three) words at a time.
Numbers – Numbers represent facts
Users tend to fixate on numerals as numbers represent facts.  Show Numbers as Numerals – e.g. use "23" rather than "twenty-three".  More info on numbers in the grammar section.

Governance & Credibility
Overview – Are you trustworthy?
Credibility is very important to users as it is often unclear who authors information on the Web, if facts and quotations are true, and whether a page can be trusted.  Content needs to be kept updated and relevant.  Adequate resources to check each content page at least once every three months is required.

Dates & Authors – Who wrote this and when
Users have more confidence in information on pages that list an author or contact and the date the page was published or last updated.

Page Updates – Last updated in 2002
An outdated page causes users to question whether any of the content on a site is relevant.

External links and citations – Cite your sources
Hyperlinks to other sites that have supporting information increases credibility and helps users assess the accuracy and quality of information on our site. We should cite our sources whenever appropriate.

Quotes – Who is behind the quote?
Users trust quotes from experts whose names and photos are provided.

Statistics – Are these facts & figures to be believed?
All statistics should be cited.

Marketing – If you say so…
Exaggerated claims and boastful language hurt credibility.  Users detest "marketese"; it has been shown that “promotional language imposes a cognitive burden” on users who have to spend resources on filtering out the hyperbole to get at the facts.

A neutral, objective writing style with factually supported claims is trustworthy and allows users to quickly scan or read content.  Slogans can be used, but should appear in the site masthead or as a sidebar.  The mission statement belongs in the about us area of the site.

Context – this heading is in the credibility section
Any page can be accessed out of context (ie. search engines). Each page needs to disclose enough information to let the user know where they are and what the topic is.  Cross-linking can be used to expand on topics covered elsewhere on the site.

Search-ability
Overview – Can you be found?
More than half of users rely on search engines to find web pages.  When a user links to a page from a search engine, they should immediately know how the page relates to their query. Highlight keywords, start the page with a summary, and follow the guidelines listed under "Scan-ability" to ensure the content of a page is immediately recognizable.  Including all of the keywords that a searching user would expect to find on a page will improve search results.

Keywords – The words typed into a search bar
All possible terms that might be credibly used to search for a page should appear in the content. Keywords appearing in the page “Title” and in the headings on a page will have the most benefit to SEO and will be most visible to the user.  Do not add keywords that are only peripherally related to a page.

Prior to authoring a page, list the most important keywords and use them to try to structure the page.

Meta Content Descriptions – Tell the user what is on your page
Each page should have a short summary included in the description meta-tag. This summary is shown below the page title by some search engines and must be 150 characters or less.

Meta Content Descriptions should make sense when read out of context and should tell users what the page is about; do not fill descriptions with hyperbole or promotional language.

Title – Be descriptive and use the keywords your user will search on
Each page must have a <TITLE> tag.  The title tag appears on the viewports top bar, the history and back button function of browsers and in search results.  Each page on a site should have a unique title.

The title tag is the single most important element in search engine optimization.

Make the first word of the title the most important descriptor of the page. Use relevant keywords in the first 40 characters, as titles are often truncated in navigation menus and by search engines.

Use the company name first for the homepage title, but place it at the end for all content page titles. Do not start all page titles with the same word: they will be hard to differentiate when scanning a list.

Headings – Just like the title
The second most important content element in search engine optimization are the headings that structure the content on a page.  Each page should have an <h1> heading that is the title of a page and <h2> thru <h6> headings that structure the rest of the content.  Headings should include the keywords relevant to the content they describe and should start with the most descriptive one to assist with scanning.

Hyperlink Text – Counts as keywords.  Ever search for ‘click here’?
The words within a hyperlink describe the destination page the user will reach when they click.  These words are considered in search algorithms and have a significant impact on page rank.  When linking to internal pages, the link text should be descriptive and contain the keywords relevant to the destination page.  Links such as ‘more’ and ‘click here’ should never be used.  Where a shorter link is desired, link “title” text can be used.

Descriptive links are very important for accessibility concerns as screen readers can read links out of context.

Keyword Density – More keywords, good – Less other words, better
Keywords that appear more often on a page with fewer words have more power in search results. See the “Be Concise” section.

Grammar & Style
Overview – This is just for the web
The grammar & style rules listed below are specific to websites and should be followed in conjunction with any other corporate writing standards in place.

Active Voice – more readable than passive voice
Active voice is clear, direct, and more succinct than passive voice.  All content should be written in active voice with one exception:  Headings can be written in passive voice to improve “scan-ability”.

Simple Language – Avoid jargon & acronyms
The language used on a website should appeal to the widest possible audience.  Convoluted syntax, specialist vocabulary and acronyms need to be avoided and there is no need to use long words where short ones will do.

As the web is a global medium, content should be written with low-literacy users in mind.  It has been shown that improvements for lower-literacy users do not come at the expense of higher-literacy users, the same way as improved usability for users with disabilities increases usability for non-disabled users as well.

Tone – Relax, it’s the web…
The Web is a less informal medium than print and a more relaxed writing style is acceptable as long as grammatical rules are respected. Caution should still be used with humour and puns that may not be understood by all readers.

Numbers – Numbers represent facts
Users tend to fixate on numerals as numbers represent facts.  Numbers should be shown as Numerals – e.g. use "23" rather than "twenty-three" – to catch users’ eyes when they scan a page.  The following rules should be followed when using numbers online:

Write numbers with digits, not letters (23, not twenty-three).
Use numerals even when the number is the first word in a sentence or bullet point.
Use numerals for big numbers up to but not including 1 billon:
2,000,000 is better than two million.
2 trillion is better than 2,000,000,000,000 as most users can't interpret that many zeros.
Use numerals for the significant digits and write out the magnitude as a word: e.g. write 24 billion (not twenty-four billion or 24,000,000,000).
But - spell out numbers that don't represent specific facts.
Grammar & Spelling – Have it checked by another set of eyes
Grammar and spelling are important for the same reasons as consistency. All pages must be QA’d by marketing to ensure proper grammar and spelling.

Web specific grammar – Some web-isms
Email vs. email vs. E-mail vs. e-mail. Use e-mail, with the hyphen and no capitalization, unless it begins a sentence or is in a headline.
WWW vs. www and Web vs. web. Use the Web or WWW in text and www in URLs.
Use a lowercase "w" when describing web pages, web surfers, or web sites.
Online vs. On-line. Use online.
A vs. An with Acronyms. Use a or an based on the acronym's pronunciation. For example, a WYSIWYG application and an ASCII file.
Set Up vs. Setup and Log On vs. Logon. Use set up and log on as verbs in instructions, such as: set up the printer or log on the network. Use setup and logon are adjectives or nouns, such as: the setup program or your logon password.
Notes About Lower Literacy Users
Overview - Lower literacy is different than illiteracy
People with lower-literacy can read, but they may have some difficulties doing so.

Inverted Pyramid – Don’t make them read so much
The inverted pyramid is especially important to prioritize information. Users who might give up after a few lines of text will have read the most important content.

Be Concise! – Don’t make them read so much
Having to scroll can break a lower-literacy users' visual concentration and they often will lose their place after scrolling.  Writing in a concise manner will ensure the most important information remains above the fold and minimizes scrolling.

Scanability – Hard to do
Lower-literacy users have difficulty understanding a sentence by glancing at it. They read word for word and can spend considerable time on multi-syllabic words and jargon.  As a result, lower-literacy users don't scan text. They have a narrow field of view and often miss objects outside the main flow of the text they're reading.

Lower-literacy users tend to satisfice – accept something as "good enough" – as digging deeper requires too much reading, which is both challenging and time consuming. As soon as text becomes too dense, lower-literacy users start skipping, usually looking for the next link.

Search-ability – Are you feeling lucky?
Lower-literacy users often have difficulty