This is the official ETS release for the GRE exam. And it is a very good guide for those preparing for this test. The book goes through a lot of background to prepare you for the Verbal, Maths and Analytical sections, including revision chapters, and sample tests and essays. But the best feature of the book are the 7 tests at the end, and to prepare for the GRE, you need practise more than anything.
But be warned: the practise tests are 'Paper-based' tests; which are not quite the same standard as the 'Computer-based' tests. For a computer test, you need to get Powerprep which is sent to you by ETS when you register for the exam. Powerprep is excellent, and as close an example to the real thing you will get.
All in all, this manual is good, but not the best on the market. For better guides, seek the Kaplan books.