You might be wondering "do we really need another ADF book out there? is it any different from the other ADF books?"
I think, you'll find that this book is targeting a different audience. This book is not aimed at teaching ADF to beginners, in fact it assumes that you already know all the basics of Oracle ADF. What this book aims to do is take you beyond the wizards and declarative features and give you recipes for more advanced ADF tasks.
The major part of the book is dedicated to a collection of how-to's or recipes such as "Setting up cascading LOVs", or "exposing custom AM methods as Web services" or more advanced things like "restoring current row after a transaction rollback", or "Using an af:selectManyShuttle component" or "Using a taskflow initializer". These cover all the layers of the core ADF (ADF BC, ADFc, ADF Faces) and also some related aspects such as tuning, logging, testing etc.
I like the way the recipes are presented. First you get a step by step instruction on how to achieve the task at hand, and then you get a "How it works" part that actually explain why you did the steps and what they mean.Then there are pointers to some additional things to be familiar with in a "There's more..." section and also pointers to related recipes or Oracle documentation chapters - in the "see also" section. This structure differentiate the how-to's here from a lot of the how-to's that people publish on blogs.
It is true that if you google for many of the tasks that are covered in this book, you are likely to find the solution on someone's blog - but I'm not sure the explanation and details on the blog would be at the level you get in this book. It is also nice to have all of these recipes in one place in a printed format with explanation that you can take with you and read when needed.
I also believe that if you'll read through the book from start to end you'll get a better understanding of the inner working of Oracle ADF - something that many developers who have already started developing with Oracle ADF will find useful. One more point in favor of this book is the fact that it uses the latest JDeveloper 11.1.2 version.
To get a taste of the way this book is structured take a look at the sample chapter published here (pdf).
All in all - this is a very good addition to any ADF developer's bookshelf.