Thanks for drawing attention to this book. I do think that the current state of denial about children and sex needs a serious overhaul and it sounds like the book takes a careful look at the question. On the other hand, I am very skeptical about children or teens wanting to have sex with grown ups. There are huge issues that materialize when this happens and I think it's better to err on the side of restraint.
On the other hand, I think children definitely should have the right to enjoy sexual activity that is age specific with each other: playing doctor, explorations, making out, etc. with lots of truthful information about disease, pregnancy, pleasure, etc.
The difficult part is for grownups to be able to be open and helpful about the subject when so many adults are so totally screwed up about it themselves.
Joanna