At over 900 pages, this book is formidable. Some beginners may be intimidated by its sheer size and weight. But, if you want thorough coverage of Photoshop CS, how to set it up, use it, tweak it and troubleshoot problems with it, then this is the book for you.
I was surprised that they started out by telling you how to build your "Photoshop System." They give advice on choosing your platform, and what you need in terms of horsepower (GHz), OS, RAM, etc. They go on to give advice on upgrading to CS and tell you what's new. (And they tell you where to find some "Easter Eggs.")
At page 555 they continue the "set-up" theme with sections on capturing images and building a digital workflow. "Capturing" covers digital cameras, scanners and photo CDs, with good advice on how to get the best image capture into Photoshop. "Building a Digital Workflow" explains the essentials of "Camera Raw," metadata and the File Browser to manage you photos. (If you're trying to capture b/w line art, it's better to scan as a high res grayscale and then use sharpening and threshold.)
They do a good job at explaining bitmaps vs. vectors, and how resampling or changing image modes affects your document. (You should use "Bicubic Smoother" for upsampling and "Bicubic Sharper" for downsampling.)
Since Bruce Fraser is co-author, the 100+ pages on color theory and management are excellent. (There are over 60 more pages on color correction, 50 more pages on spot color and duotones and yet another 50 additional pages on tonal correction.) If you buy this book, you don't need an additional book on color management.
I personally got a lot out of Chapter 10, which covers sharpening. It gave me a better understanding of how it works and how to do a better job when retouching photos. I plan to re-visit page 626 when I need to convert color images to grayscale. And page 636 has a technique to use the clone tool and stroked paths to automate removal of powerlines, long scratches, etc.!
Of course, they cover more stuff, like getting more detail in shadows, text and typography, photomerge hidden features, and how to apply those nifty filters and effects.