I used this guide for my one-week driving vacation on the Loire Valley and it was of great help.
It's hard to decide where to go, especially when we're visitting a large region (as opposed to a city), and idle driving must be avoided. The guide helped a lot in the planning. (AA maps, ISBN 0749544112 and 0749544066, which I also bought from Amazon, were of paramount importance too.)
I only visited the Anjou and the Touraine regions (which are only a part of the Loire region), and for what I could see for myself the information in the book is accurate.
Taveler's needs sections (specially 'Where to stay' and 'Where to eat') were also of significant help: I stayed in two of the suggested châteaux and dined in one of the restaurants and couldn't be more satisfied. But I would add some suggestions of my own...