I'm especially bothered by the focus on super early milestones which even DYS has abandoned as part of the application. There is so much variation for so many reasons which have *nothing* to do with intelligence that the focus on behavior of infants seems excessive.
Davidson hasn�t abandoned the issue of early milestones. It is now just optional to submit ages rather than required.
As Kriston and others have stated often, I think the book is a great help to the parents of kids who do meet the early milestones, but not a reason to rule out giftedness if a child doesn�t.