The predictions in this book are interesting and very detailed: everything from economics, geopolitics, specific technological advances (mainly in military weaponry), population and ethnic demographics, and even the next world war and how it will be fought. I can't underscore this point enough Friedman is very specific in describing what will precipitate the next war, how it will be fought, who the players and allies will be, and how it will be won and lost. Many of the details will surprise you.
This book's value is more in its entertainment than in its likelihood. That's not meant to denigrate the author, who is a very brilliant strategic thinker. But there are many areas in which the predictions are either unimaginative or highly unlikely. For example the author's futuristic economic predictions are simply arrived at by looking at past economic cycles and presuming that they will repeat precisely. He also presumes some drastic and unlikely geopolitical shifts without explaining how they will come about (e.g. the reuniting of the two Koreas, the formation of a Turkish coalition that includes Iran and Iraq) and he also predicts an unprecedented military buildup of futuristic technology but does not explain how the various nations will pay for all of it. He does not even really address the exponentially growing US debt in any detail, but presumes that it won't be a problem. Amid all of these criticisms however, it must be conceded that the author makes a valid point when he reminds us that history (indeed, recent history) is full of examples of things that people would have thought would never happen in a million years.
The author also leaves out some very important considerations of futuristic importance. For one of these, global warming, he concedes that he has not adequately addressed it, and then proceeds to discuss in the most superficial and cursory manner. He also places great stock in control of the oceans for strategic military reasons, but fails to explain why this will be important in an age of rapid air travel. Other issues such as health care and the problems of poverty are not really addressed, except as part of a basic assumption that in the future these things won't matter, much like how past futurists predicted that we would have flying cars. Virtually nothing is said about Africa. Friedman presumes the continued existence of a very large military industrial complex (probably his safest prediction) any by implication suggests that this and a continuing government erosion or privacy are good things, or at least things nothing to worry about. The author has missed the boat on a number of issues that merit discussion and which would have made for interesting reading and speculation. Too many significant global problems are summarily dismissed in a sort of "trust me, things will work out" manner. Friedman's focus really is on geopolitical alignment and how global warfare might look in 2050. (I'll give you a clue: Newt Gingrich will feel vindicated.)
For the reader who approaches this book thinking that it will give some insight into what life might legitimately look like in one's latter years, the book won't be of much help. It also won't offer any investment advice or help in planning a happy retirement or really any sort of personal planning. The book doesn't inspire any confidence about its accuracy with domestic predictions, and its geopolitical predictions read more like fiction than futurism. But the book's strength is in how the author shares his vast knowledge of world regional politics. Friedman does an excellent job of telling us how we got to where we are, which in turn helps to enable all of us to better think for ourselves about the direction we're heading as a society. That's an accomplishment that should make any author proud.