Are you all fans of Goodreads? I'd joined a few months ago, entered a couple of books and then left it for dead. I didn't really see the point. After the initial entry it felt a little too much like entering my snack calories into FitDay - a chore with not much reward.
But then one day I poked around a little bit and I was hooked. Hooked! Really, it combines the best of what I love from online book browsing with my love of CIA-level-profiling of the people I stalk online. I've been burning up my library card checking out stacks of books recommended by my online peers and they don't even know it! Like Facebook, it's the ultimate way to get personal information without having to employ any actual interpersonal skills. Huzzah!
Plus, once I started entering books I'd read, forget it. My All or Nothing Switch (on which I'be been trying to install a dimmer for years) was flipped and I voraciously ripped through my last three years of B&N and Amazon orders to post my books. In the end I got a pretty collage for my blog. Bonus! When I find some time I'll try to work in all the books I've bought in meatspace as well, which takes actual work rather than just cutting and pasting from Amazon. So, yeah, it might be a while.
I urge you to give Goodreads a try - more for book recommendations than for a catalog of your own reading. And please, if you sign up, make me your friend so I can peruse your books as well...