Booker.io - Booker is a networked book discovery platform to help people find must read book through people...
Goodreads - See what your friends are reading.
LibraryThing - A home for your books.
Read This Twice - Verified book recommendations from people we look up to
BookAuthority - BookAuthority collects the most recommended books on business, technology and science - as featured on CNN, Inc and Forbes
GoodBooks.io - Largest curated collection of 8,500+ book recommendations.