The PC-BSD Book Forums allow readers to share their errata, requests for second editions, discuss book pages they found useful or which need improvement, and provide book reviews.
While I haven't seen a full review yet, I've heard from several readers who have received their copy of The Definitive Guide that they are enjoying the read and have learned a few things along the way (always a good thing in a technical book...) The writeups I've seen so far include: