This book did an excellent job providing examples of how history may not be what we think it to be, challenging preconceived notions that have been drilled into the brains of human society for the past couple of centuries. It was awesome learning about some of these civilizations.
However, I do have several issues with this book. Right from the get-go, it feels like the authors are berating you for reading the book, assuring you that you do not know anything and that they know everything, and that they are going to totally reshape history. It took me much longer to get through the beginning of the book than the rest of it for this reason. I love history and social science, but I hate condescending authors.
Another issue I have is that many of their arguments are in fact non-arguments. The issues with this are several fold. One issue is that they sometimes seem to be arguing against an invisible enemy, as if they have something to prove to them. A lot of their arguments are against pop historians and pop social scientists, and I do not think that most academics in these fields actually think this way. And while the authors provide compelling evidence for their arguments, it never really links quite right, so I end up finishing a section detailing some historical occurence thinking "So what?" No strong argument is made except for "hey, history isn't what you think it is." They are also quite repititive, which gets frustrating. In short, this book was too long for what the argument ended up being.
Another gripe I had had with this book was their constant referral to the "state," quotation marks included. I agree that statehood is a strange and relatively new concept, being a student in international affairs. But I am not aware of many experts applying concepts of statehood to prehistorical societies. But the authors insist that this is what is happening and that they are the ones saying otherwise. It's a strawman.
Of course, I don't have much background in archeology and anthropology, but neither do most people reading this book. Therefore, I think it is dangerous to only read this book and hail it as complete truth or complete falsehood without consulting other arguments. So I think it is a bit silly to not only be a bit degrading to the reader but to other authors as well (a lot of whom, again, aren't really the main authorities of the fields they are writing in).
So, to sum up: this book was great at opening my eyes to other possibilities and a fresh look at history, supported by multitudes of compelling evidence; however, the main issues of this book (which cannot really be overlooked) lay in the writing, the organization, and the arguments. It's a shame that one of the authors died because this book would benefit from a rewrite.