I was disappointed in this book. It is quite long (352 pages plus notes) and unlike most of Lewis's work I didn't find it to be particularly entertaining. It contains a lot of biographical material about Kahneman and Tversky which (while intermittently interesting) isn't especially relevant to their professional work. It is repetitive in places (for example colleagues and students describing how brilliant they were). It abruptly introduces other characters and then drops them without really integrating them into the narrative. It contains chapter notes at the end of the book but no index. It suggests that their work was very important but doesn't really explain why.
Nor did I think it was especially instructive. It isn't technical enough to be a good introduction to Kahneman's and Tversky's professional work. I have previously reviewed books by Ariely, "Predictably Irrational" and Thaler, "The Winner's Curse" which discuss related work on decision making. While I didn't recommend them either they would provide a better introduction to the field.