2002. I read a big part of the book several years ago. The author goes far beyond the available evidence, and most other scholars are not convinced by his conclusions.
A fair question, as winning that prize puts a book in good company. I'm trying to remember what other books about science were published that same year.
Of the author's main points, many waves of settlement, some earlier than previously estimated, is still a controversial point. (I have just been reading books on physical anthropology about the genetic evidence on this issue, and his hypothesis is not well supported.) High levels of cultural advancement in pre-Columbian America is still a controversial point (although partly controversial as a matter of definition, of course, especially for the regions of America without writing, much as is true in Africa). His main point that is best accepted--and still deserves to be better known--is that the first settlers of America didn't "live with Nature" but actively shaped their environments, notably through use of fire to promote agriculture.
