More than just a design book,
This review is from: Designing for the Social Web (Voices That Matter) (Paperback)
If you want to learn how to create relationships with your users rather than have them visit and leave, then read this book. It's not just a design book and it's not just a social media book.
It is well written and you can easily skip to the bits that concern you. Porter explains social media in a way that few people manage to do as simply.