3.0

This book has a lot of good information in it, and most of that is backed up by evidence (there's a long section of references at the back). The evidence is hidden though so it's hard to follow the trail as you go; I can see why (it's not an academic book, and it's obviously going for a younger audience) but I'd have preferred explicit references. (Particularly given the advice in the book to give credit where it's due!)

The style of this book is very informal and... American. I found it grating to begin with, although I relaxed about that once half way through.