I confess that this book surprised me positively. The authors did a great job in mapping the traditional versus agile approaches, focusing to explain it to traditional project managers who wants to bridge to agility. It's important to note that the authors were helped during the writing by known names as Mike Cohn and Ken Schwaber.
I gave four stars because I believe the authors should have given more emphasis between the scrum master and the agile project manager roles, since it will not always be performed by the same person.
It is a good guide for those project managers who use techniques from the Project Management Body of Knowledge (PMBOK) and wish to know the difference between the way they are currently managing projects and Agile. The book's central theme is to map the different areas of the PMBOK to their Agile counterparts, identifying the processes and tools it makes use of.