...this confuses me. So...it's like tumblr...for books?
Either way, I'm mainly on Goodreads. I do occasionally come here, and also do periodically import my shelves from GR here, but GR is a more sure bet for contacting me.
It was actually rather adorable. 3 stars, though, because while I understand that it was free, there were spelling/grammar mistakes that I feel a quick proofread should have caught.