This book contains some really good stuff which will improve your photoshop skills and make your photo's better. There is a section on most of the main area's of photography such as portrait fixing and landscape altering.
One of the most useful techniques that I learnt was how to remove unsightly objects from a photo such as TV antena's. It is also good on starting to use layers to create effects.
The only bad thing about the book is that towards the middle and end of the book simple things are still explained in detail which you know how to do already from earlier in the book.