I finished this recently, it having superbly passed the Tube Test (i.e. does it grip my attention strongly enough to encourage me to get it out each hot, stinky tube journey to and from work).
Based on his newspaper columns exposing and explaining examples of 'bad' science and bad reporting of science, it's both entertaining and informative in a really useful way.
Like most people, I undoubtably don't question what I read enough. And it's probably only when someone's challenging an assertion I blithely make that I stop to think where I heard it and whether I can trust that source.
The book tackles quite obvious targets, such as homeopathy and Gillian McKeith, but instead of just providing counter arguments, it really tries to provide the readers with the tools to assess what they are reading about anything science-related for themselves. Now, I'm not sure I'm really going to start chasing up academic articles, checking out reviews on the Cochrane Collaboration site, or reading deeply into statistical methods of studies, but I do feel like I am reading things with a more healthily sceptical mind, and spotting potential mistakes much easier.
Heartily recommend it if you're interested in thinking a bit more about the health and science stories you read.