Very much like the virtual bookshelf in Facebook except this offers a lot more than just the covers of books you like. Recommended readings, quick links to places it can be bought, or the LOC for more information. If you tell it where you are located, it will even pop-up local resources to buy the book or a listing of local libraries that may have it.
The recommended reads based on "The Poems of Charlotte Smith" were a little disappointing since it only recommended other books by her, but that is a narrow field and searching for someone a little more mainstream might yield better results.
There are also different interest based groups you can join and an online discussion page. Overall, I like it. I'll have to add it to my favorites.