This is a beautiful book. The illustrations featured are fantastic and the designers are hugely talented. There is a good range of illustration styles featured. But while the book is inspirational, it's not hugely instructional on the real detail of exactly how the designers are using the software to achieve their results.
This book is more an ideas book than a how-to, so it is less dependent on the version of Photoshop you are using. Beginning to intermediate users would find techniques they perhaps hadn't thought of using, with a guide of how to proceed. For complete beginners to CSx or Photoshop, this book would provide an idea of the sort of effects that can be achieved, along with some ideas of where to start practicing.