Just came across an excellent article in Publishing Trends that talks about how publishers are using Twitter for book promotion -- and to win friends, allies, fans, and potential readers down the road. Although the article doesn't extend the advice to authors, it's clear that authors should follow the same Twitter techniques that are working for publishers.
The article boils down to this: Twitter doesn't do a whole lot for a book promotion campaign if publishers and authors keep offering up 120-word sales-oriented tweets to their followers. Instead, Twitter works as a networking and community-building tool if publishers and authors reveal something about who they are through their tweets, and offer comments to other Tweeters so they can develop online alliances. Twitter users who enjoy the personalities behind the tweets are likely to tune into whatever twitter users are doing, whether it's book promotion, conceptualizing new books, or revising books that haven't yet found a publisher.
So if you want to tweet to make friends, and you trust that some of your friends will want to buy your book someday, great. But if you want to use Twitter to command strangers to click on a link to buy your book on Amazon, forget it. There are too many tweets competing for Twitter users' attention to focus on tweets that are all about demanding rather than gentle persuasion.
