The Whole-Brain Child is part of the current parenting zeitgeist mostly coming out of Southern California psychology practices. Like many popular science books, it is repetitive and could probably get away with half as many pages. But, I don't think publishers would take a book that short because people don't take very short books seriously. So you fluff out to 200 pages. However, the overall message is good and it is an easy read.
I definitely recommend this if you are doing the rounds of parenting books. I waited until now to read it because I knew it would be less relevant for a very small child. Even still I probably got in a bit early as most of the material is more suitable for older children.