What Is Goodreads?
Goodreads is the largest site for readers and book recommendations in the world. We have more than 8,700,000 members who have added more than 310,000,000 books to their shelves. A home for casual readers and bona-fide bookworms alike, Goodreads users recommend books, compare what they are reading, keep track of what they've read and would like to read, find their next favorite book, form book clubs and much more. Goodreads was launched in January 2007.
It's basically Facebook for books.

Made a Retroids group for people to join, not sure how many people already use Goodreads but you can join here:

http://www.goodreads.com/group/show/...troids-members