Sitepoint has a nice newsletter from Moreover of pointers
to what's new in web development, and their own list of tips.
From this week's edition:
The rule of five (plus or minus two) does apply on the web.
Too many choices and users become confused. Want proof? Check out
Overstock.com, a perfect example of what not to do. It tries to
offer everything and because of it users will be hard-pressed to
find anything.
An information architecture with several layers would have suited
Overstock.com much better. Just imagine, Amazon.com listing all
book or music categories on their frontpage.
A combination of both task and goal oriented navigation may work
well for some sites. A goal is when you want to get to a specific
page (the portfolio, for example), while task oriented navigation
is about doing something (such as finding out who to send a
resume to).
Just remember to visually separate the two types of navigation,
either visually on each page or via a hierarchy. Offering both
types of navigation links from the same navigation bar on the
same page can cause more problems than it solves.
Both types can co-exist on the same site, or even the same page,
but not in the same navigation menu.