Note: This is not a review about the whole book, as it was a military expose on David Petraeus and most of the 'facts' about the military went entirely over my head. I did this for a friend, looking for bias in the book.
Now, on to the actual review, to answer his question. Is there bias in this book? Yes, there is bias. The author seemed intent on defending Petraeus despite trying hard to seem objective and unbiased. Most of the book went over my head, and from what I could tell, the author seemed to believe that Obama threw the man under the bus after the plan in Afghanistan went under. The prose seemed complicated, and it felt to me as if one would have to have an intimate knowledge of the military and its workings to understand even the slightest bit of what went on.
Most of the book was about him growing up, his meteoric ascent to the top of his class in school, then his numerous accolades when the daunting task of Afghanistan presented itself to him. I will say this, though--I admire the man's humanity and resilience, his sanctity for human life. I admire his approach to the whole situation. In my opinion, based on the facts presented in this book, the man did his best with an already bad situation.
(Note to Tim: She made no mention of an attraction to Petraeus, but there was a definite bias there. She supported him, flat out.)