This book seems extraordinarily well researched. The writing is good and there are several very thought-provoking pieces of insight. My biggest problem with it is that Charles Mann lacks the proper credentials to write it and I lack the expertise to judge if he did a good job with it.
I can at least weigh in on the areas that touch my expertise. The economics portions are reasonably accurate and thorough. He misses the mark on a few occasions but there is enough correct and balancing information to make it a good effect. The descriptions of the economic effects of the silver trade regarding monetary policy are apt. The economic arguments regarding slavery are apt, I can’t speak to the takedown. I also can’t speak to the ecological and agricultural arguments.
Sorry, I wish I could be more helpful! I’m planning on learning more about the subject, maybe I can update it once I’m in a better place to judge. in the meantime, here’s a more expert review.