I wish I could find a better reference right now -- mostly I've seen problems brought up in blog comments, and those are pretty effectively swamped by heavily linked reviews. My recollection is that the problem is mostly with genderqueer and feminist folks who object to Colapinto's binary-gender-essentialist slant. My recollection of the book is that it presents the case in a "boys are inherently boys at all times" way rather than your (and my) equally reasonable "someone was assigned a gender they were profoundly unhappy with" perspective. ISNA (http://www.isna.org/) loves it because it's anti-surgery, which I totally agree with, but I did get grumpy about the essentialism. Some of the reviews seem to disagree with my perception that Colapinto didn't address trans and intersex issues very well, so maybe I should reread.