Found via Column Two:
3-clicks to anywhere
People often ask me whether they should make sure all of their content is available within 3 clicks (“3 clicks from where” is usually my first question). I can’t remember where this ‘rule’ started (Nielsen?), but common-sense would tell you that it is sensible only on smallish sites.
What if those 3 clicks are into the unknown? A user can become lost in 3 clicks as easily as 5, 7 or more.
What is far more important is to get users following the right path. When they know that they are going in the right direction, they stop counting clicks and start getting engaged with the content.
This is a good reminder to question the assumptions upon which you base your rules of thumb. Lots of good links her full entry and comments. Go check it out.