Peter Woit has a blog with the same title as this book, which has a popular following, and from the advanced sales it looks like the book's performance may be equally impressive. Woit's arguments against string theory are certainly very persuasive. One reads how initial hopes that the theory would lead to a unique explanation of quantum gravity were disappointed, and how the predictions of eventual success of the theory are being pushed ever further into the future.Woit also expresses his frustrations at some of the failings of the academic establishment, which will make the book useful reading for anyone considering a scientific career.
The trouble is all that is in the last third of the book. Woit clearly feels that he has to give some background to the subject, and the first two-thirds are taken up with a history of theoretical particle physics. Now I appreciate that Woit is trying to make the book into a consistent whole, which is not possible for a blog which relies on external links. However I think he is facing an impossible task trying to explain gauge theory and group representations to his intended audience and I feel that many readers will struggle and give up with this material and the rest of the book will remain 'not even read'. That's not to say it isn't well written - I found that it helped to link together various parts of the subject - but I didn't think it was needed in order to appreciate the rest of the book.