If you want to get started with Irrlicht and don't want to wade through API docs and samples, you'd rather learn it in book format, then this is a good book for you.
Emphasis is put on examples and results-driven learning. Thanks to the power of Irrlicht, most examples are just a few added lines of code, or they build up in steps that are each just a few lines long. At times, I almost saw these examples as recipes. For example, one of the very first actions is to create the IrrlichtDevice object. There's a nice step-by-step explaining to create your main method, initialize the IrrlichtDevice with createDevice, check the pointer, and then drop the device. The next examples build on this one with more steps. And when the chapter is over, you have a working demo - essentially the equivalent of one of the samples included with Irrlicht, but instead of looking at the sample's finished code, you've built it up step-by-step in the order that you would actually build a program.
Along the way, explanations and advice are also given. When a new function call or type is introduced, it's explained. When a new 3D topic is introduced, it's (very lightly) explained. Never, along the way, is anything confusing. Every example is introduced first in the steps to implement it (so for example you could just follow the steps in your own program to add the feature), followed by an actual complete code sample of the feature. This makes the usage abundantly clear. Also, screenshots are used throughout the book, both on every sample and to supplement explanations of theory.
Now, there are things this book is not. It is not an introduction to 3D theory at all. The cover even says, "learn by doing: less theory, more results". And indeed the use of Irrlicht requires very little 3D knowledge, since Irrlicht abstracts away the low-level graphics operations for the user. It's probably not a good reference - sure, you could check a section to see how to use a certain feature, but for anything non-trivial you're going to need to look elsewhere. It's not a start-to-finish book on developing an application; instead, every chapter builds up a new sample application using the new features introduced in that chapter. And of course it's not a game development book - game development is only one of the uses for the Irrlicht engine, and while games are mentioned in a couple of the topics in the book (sprite sheet rendering, rendering and moving a 2D ball), a game is not made.
It's also not perfect; I did find one logic bug. To be clear, I did NOT see any errors with the usage of Irrlicht. And there is the occasional grammar error, which I certainly excuse because the author's native language is not English. Nothing that cripples the usefulness of this book as a beginner's guide, though.
In summary, the book is exactly as its title describes - it is a beginner's guide to Irrlicht. It is not a guide to 3D concepts, it is not a reference manual or advanced guide. It does not instruct you on how to extend Irrlicht. It isn't a guide to making a game with Irrlicht. But it is a complete walkthrough of every feature of Irrlicht, explaining each feature with explanations, examples, and screenshots.
I've given it 5 stars because I believe as a beginner's guide to Irrlicht (which is exactly what it advertises itself as), it hits the mark. I would love for a more advanced Irrlicht book to come out, but this does not take away from the fact that I think this book is extremely useful to someone who has no prior knowledge of Irrlicht other than its purpose/features, and learns best by reading a book.