I agree with those reviewers who found this book somewhat less awesome than they initially anticipated. Coming from a math background, and as surrounded by technology as I am, I think that the book would have had more of an impact with me if I knew less about these issues already. And that's why I'm giving it such a high rating: it does a good job educating, and I like that in a book.
Stephen Baker's tone is conversational and analytical as he takes you through successive chapters that introduce us to the Numerati, the mathematicians, engineers, sociologists, and marketing gurus who are analyzing and modelling humanity. The Numerati's interests are varied, from the workplace to the bedroom. As a mathematician, I enjoy books that educate people about the real-world applications of math and remind them that it's not just a dry, dusty discipline full of formulas and equations.
The medical chapter intrigued me the most. Baker interviews several people working with Intel on technology for modelling people's behaviour at home. These machines would alert doctors when a patient deviates from regular behaviour, thus allowing doctors to know if someone's weight dramatically decreases or if an elderly patient has fallen. The potential applications of our ability to model and predict human behaviour have immense implications for improving our medical industry, which is plagued with difficulties in both Canada (go universal healthcare!) and the U.S. (with its privatized healthcare).
Baker does mention privacy concerns, but he mostly glosses over these, pointing out that there is a difference between disclosing one's "personal data" and one's "identity." I see his point. I also see why many people are concerned about the role of privacy in the Google age. I would have liked to see some more specific information on privacy--the book in general feels short. In places, it could be much more specific, expansive. But I suppose that Baker wanted to keep it light enough to attract the curious reader, and I will forgive him for that, because it was interesting and informative. I'd read a sequel.