Goodreads - See what your friends are reading.
lib.reviews - a free, open and not-for-profit platform for reviewing absolutely anything, in any language.
Riffle - Just good books and the readers who love them.
LibraryThing - A home for your books.
CNET - CNET is a website that provides you with the latest tech news and tech reviews. The homepage of the website is a huge feed of the latest tech stories that would take you hours to sort through. Read more about CNET.
Readernaut - We are a small community of readers, sharing our adventures and supporting each other as we persue a life of learning.