Tim O'Reilly and Sarah Milstein are two of my favorite tweeters, and they've just written The Twitter Book, a pleasingly-designed 240-page guide to making the most out of Twitter. The hard copy won't be out for a little while, but you can buy the PDF right now for $15.99. As Cory says on the cover blurb, "This book delivers a bunch of sensible, down-to-earth material on using and enjoying Twitter.: I couldn't agree more.
This colorful guide will teach you everything you need to know to quickly become a Twitter power user, including strategies and tactics for using Twitter's 140-character messages as a serious–and effective–way to boost your business. Co-written by Tim O'Reilly and Sarah Milstein, widely followed and highly respected Twitterers, the practical information in The Twitter Book is presented in a fun, full-color format that's packed with helpful examples and clear explanations.