Full disclosure: I was the technical proofreader for this book. Before you yell at me for anything I missed, please know that I was called on at the very last minute to help out. Nonetheless, I did the best I could in the time provided, hand-entering most of the examples directly to make sure they worked as expected. Also, while I will be getting compensated for my proofreading of this book, my earnings are not dependent on its success or failure.
Having said all that, I highly recommend this book if you're looking for an introduction to the Play Framework from a Scala perspective (there is also a Java-based book with a similar purpose being published by Manning later this year). There are certainly things it leaves out, such as testing (a big oversight, as Debasish
has pointed out in a recent tweet), embedding in existing SBT projects, etc. But for a mostly comprehensive understanding of the core functionality, this book is very useful. It's also well-written, providing clear explanations where things might not be entirely obvious. It does assume some familiarity with Scala and having exposure to Akka, which Play uses for various purposes and provides as a utility for the user of the framework, would be helpful, but one does not need to be an expert in either to find this book useful.