I've been following the arguments made by Peter Woit against String Theory for quite some time, and it's a pleasure to be able to have them all in a single volume. His arguments are very persuasive, and his writing clear and to the point. This, however, is not a book that the general audience will find easy to follow. The earlier chapters recount the canonical story of the success of the particle physics in the 20th century, and if you are familiar with that story you can safely skip these chapters. The later chapters are the really interesting ones, but unless you have at least some familiarity with theoretical particle physics and the modern mathematics, you might find yourself lost. Even with that caveat it is still possible to appreciate the central theme of this book: theoretical particle physics took a wrong turn somewhere in the late 70s and the early 80s, and has never been able to recover from this. Woit is appealing in this book to the practitioners in the field to be more honest with their assessments of the direction in which the theoretical particle physics is headed, and the lack of any meaningful progress.
Unfortunately, I am very sceptical of the potential impact of this book on the field of particle physics. The Emperor is naked, but he is perceived as irrelevant as well.