Note: This review is a slightly modified version of what I posted at Amazon.com.
If you are a hypermedia developer you should read this book. If you are building web apis to reach multiple devices then you should read this book. If you are building web apis that will be around for a long time and evolve over many versions, then read this book. Hypermedia systems have been around since the dawn of the web, however they have mainly been HTML pages offered up to a browser agent. It is extremely rare that you see the usage of hypermedia in web apis / machine to machine scenarios.
Hypermedia is basically a black art that very few folks actually understand. I experienced this first hand when I was the PM for WCF Web API as hypermedia was something that we wanted to be able to support. I immediately discovered that there was very little literature on the concept, there was no definitive reference to turn to. The guidance was mainly spread through a set of articles and through thousands of mail threads. Mike is one of the few who actually gets it having many years of experience building such systems. He is one of the foremost experts on the topic. Just head to his blog or the REST discussion list and you’ll see this is the case.
The one thing I would have liked to have seen Mike elaborate on a bit more was why hypermedia itself was important. Throughout the book it does become more self-evident however for one who doesn’t understand what it is I felt that the book could have laid more of a foundation / done a bit more selling on the value. Mike does plenty of that in his blog though.
If you are building RESTful systems particularly in node (though the guidance is general applicable) then I highly recommend this book.