I agree that this is not a book for the beginners, but nevertheless it started with the very basics. I was impressed about it though it is from a Cookbook series.
The approach in the book is: if this is your problem, here's the solution, followed by a discussion which provides great amount of detail about the concept or function. This format allows the book to be used as a reference guide as well as it will assist us to jump to a point directly. The book illustrates plenty of functions of R in this fashion.
There are parts of the book that educate us about Statistics itself, but prior knowledge of some Statistics is a must if you want to make the best of this book.
The author shows examples from a variety of libraries - MASS, Cars93, zoo, XML to name a few. Enthusiastic readers will explore the data sets in these libraries and become more hands-on. The chapter on Useful Tricks exposed many of the "helper" functions. These add to the convenience while working with R.
The code samples for the book seemed incomplete when I downloaded them. But this worked for my benefit in the sense that I spent more time actually writing the code or creating the data myself - helped me get a little more comfortable around it's syntax. Blessing in disguise I guess.