Deke McClelland presents an entirely new way to approach masking in Photoshop CS4 Channels & Masks One-on-One.  The idea of using an image to select itself is a wonderful concept and can significantly reduce the amount of time put in to creating selections.  Deke starts out thoroughly explaining the existing selection tools, such as the magic wand and magnetic lasso, even giving special advice on when and how to use them properly.  The real meat of the book comes a few chapters in, starting with composting with blend modes and going on to selecting with channels and other more advanced techniques.  I had the privilege to sit through Deke's tutorial on making selections with the calculations command at Photoshop World 2010.  He explained in great detail how to properly use the technique, it is explained equally as well in this book. 

But the book is only half of what is offered here.  Deke also includes a DVD with hours of tutorials, walkthroughs, and sample images used in the lessons in the book.  The disc also contains Deke's very own photoshop palette, providing quick access to all the tools you need to make that perfect selection.  All-in-all, this is a terrific offering from one of the top photoshop guru's.  I highly recommend this book to anyone looking to expand their repertoire and learn new, time saving techniques in Adobe Photoshop.