This little book is not just a beginners guide to twitter. As someone who loves twitter and has used it for 6 months it enlightened me about many aspects of twitter protocol and pointed me to online tools like twitpix and tweet deck etc that make it more fun to use.
There's advice on who to follow, celeb users, twitter jargon, user stereotypes and a short history of its rapid ascendancy as a social networking site- such as when Stephen Fry took it mainstream with his famous `stuck in a lift' tweet.
It's written with a sense of humour, and as a quick reference guide it's a perfect summary of what twitter is all about, and how you can join in without making a faux pas.