A guiding heuristic for intranets, websites and pretty much any online content is to keep your pages short. Minimise scrolling where possible, and don't forget the inverted pyramid style of writing.
Remeber the 23 page Ars Technica Review of Snow Leopard? There's a few reasons why that was 23 pages, one being they wanted to keep you on the site (so a PDF download wasn't appropriate), another being it was easy to segment, another being it made reading the magnum opus of software reviews that much easier.
Over on UIE.com there's a great article from Ginny Redish, called, 'Breaking down documents for the web'. This is an excerpt from Ginny's book, Letting go of the words: Writing web content that works, and it makes a lot of sense, with some great examples and screenshots of how companies display content effectively, including Nokia (right), BoA, the Pension Service and more.Essentially, Ginny says that online, we need to think about topics and effective segmentation of content that's supported by a solid database, good navigation and effective search. Offline, think user manual: online think index cards for specific topics. The dynamics are significantly different.
See the article here, and given how well this excerpt articulates an often hard to understand topic, I might have to go find this book.
