I’be been using GoodReads for over 5 years now, and it’s nice tool.
It keeps track of your books with a feature named My Books.
Plus it integrates with Amazon, so any books you buy there are available inside GoodReads. And it integrates into many popular social networks so you can find out what your friends are reading and share with them what you are reading.
You can set reading goals, and see the most popular books overall or across your friends.