Oooo, back to something that seems academic and sophisticated - so I'm going to say this is a great site even though I haven't had a great play yet!!
One tiny issue, possibly - many of my very favourite books that I have entered have been printed many times, so they're all not "one book". I wonder if that is a search issue later (when looking for other related books that I might like), but I doubt it will be a problem. I just love how you can type in an author (such as Douglas Adams) and expect to see a few books, but there are heaps!! And one's I hadn't known existed - I take it that that is when a site like this becomes really cool. And stops you going to bed when you are knackered.
A first play here indicates that Google Books would work very nicely together with this site. Still nice to search by keyword in GB.
Nevertheless I like this one, will be sticking a widget on my blog (whatever the hell a widget is, I expect we learn that later???).