A lot can be learned about useability from studying what the big boys do with their sites. I especially like the way big companies make you jump through four or five pages of "Was this what you were looking for" as you try to get to the contact us page. I find it frustrating, but also understand that the support costs of these organisations must be enormous from people who simply don't read.
I've helped a few people set up their websites. We try to make everything as simple and as useable as possible. But they still get questions like "What are your prices" when the "Prices" button is large, readable and directly above the "Contact" button. Then there's "Send me information about XYZ" (Did they not notice the huge link to information about XYZ). Some people I know just resort to sending a big PDF dump of their website to these people via email.
I think one of the problems these days is it is too easy to ask a dumb question via email - in the past you'd have to admit to someone over the phone that you hadn't bothered to properly read the material they sent to you in the post - so people might have actually tried to read.
We live in changing times...
Dave - Amazon do some good stuff, though not sure how those text stats would be useful. We already have a related threads function which is automatically inserted into new threads (kind of like the same functions on amazon for selling you related books?). I'd love to see more automated stuff like this come into forum software including automated moderation. Imagine: "Are you sure that was the right area for your message, the system recommends that the following areas may be more relevant".
Even better would be an annoying paper clip - "Are you sure you want to start a new thread on that topic? It's been done to death already". Now that would be progress