The book works thcrough various projects, both realistic and cartoon images, still and animation lighting, texture creation and rendering. I would recommend this book to anyone wanting to learn more about Blender cycles. Personally I would have liked to have more images of rendered views throughout each project not just node setups.
Pros - cookbook style with many examples - thorough coverage of all things Cycles - gentle learning curve - some really great materials (especially carpaint and food) - addresses lighting as well - plenty of relevant external references
Cons - could do with some detail renders of the individual materials - doesn't cover volume shaders
The Cycles rendering engine has been available for some time now in Blender but it is still hot because it enables the artist to produce great results. However, its many options can overwhelm a person just starting out, so Bernardo's cookbook is a blessing both for beginners as well as for more accomplished artists.
The book is well written and covers almost everything from basic node setups to very complex ones, including subsurface scattering nodes and script nodes. The illustrations of the node setups are also very clear and although the book's style is a cookbook, the reasoning behind the creation of the materials is often explained as well which really helps to understand why the materials are set up the way the are.
I also like that the is a fair amount of information on lighting because now matter how good your materials are, without proper lighting your render won't shine. The book presents some useful lightning setups and covers both mesh lighting and HDRI lighting quite well.
The criticisms I have are minor indeed: the book doesn't cover the new volume shaders but this is of course not a fault of the author. Cycles evolves at a rapid pace and at the time of writing volume shaders were not yet available.
Also it would have been clearer of some of the many materials presented in this book would have closeup example renders; now there is just a larger overall render of a scene at the beginning of each chapter which doesn't show the smaller details very well. Of course the sample scenes are available to the reader so you can render them yourself but it would have made for an easier read.
All in all I really enjoyed reading this book and in my opinion it is one of the better ones on Blender published so far.
Conclusion A well written book that delivers what it promises. Well worth its money. (But consider buying the e-book because the printed version is in black and white)