Just last week I had two people email me with similar site ideas to hn-books.com, and when I launched hn-books 2 completely other people emailed me that they were working on similar sites.
Must be something about hacker books that's in the water. Lots of sites with lots of features and such means better resources for all hackers, plus lots of folks getting experiences doing stuff like this. Most excellent!
Since I've done this, I guess I should say something pithy or insightful. I think the trick is the navigation piece. I see you have categories -- that's probably a good place to start. I started with questions, you can go to my main page, click on the hacker-related question you have, and be presented with a sorted list of answers based on your experience. (see http://hn-books.com/ )
I'm not sure if questions are the way to go either, though, as there are a zillion questions hackers might ask. I'd still like to see somebody come up with some new ideas in this area.
I also ran into the "just what are hacker books, anyway?" question that we get over here all of the time. I finally said screw it, I'll just put things that I believe are hacker-related. But I don't think there's any easy answer to that one, either.
Outstanding site, though! I hope some of these other guys that have spoken to me will post what they've done as well.