Excellent book, very descriptive technical details on how each tool works, how it should be applied with useful examples.
Very different approach to Scott Kelby's CS4 for Digital Photographers, it you want a deeper understanding of how Photoshop works get this book, if you want to know how to just fix an image problem then Kelby's book may be better for you. I have both books and often refer to Kelby's first and when requiring further explanation refer to this book.
The tutorials on the accompanying DVD are also very good.
I`ve also bought previous editions but the new information on Camera RAW and Black & White conversion makes this edition well worth buying. Thoroughly recommended.