I have written a chapter-by-chapter review of this book on [...] the first part of this review follows:
It is practically impossible to write a book that covers everything in SQL Server 2012. However, if you ask a group of SQL Server experts to write on topics that interest them, you'll end up with a book full of enthusiasm and detail - this is such a book...
I expected the book to be mostly innovative, but it is probably 60% new material and 40% rehash of material available elsewhere.
The chapters fall into three categories, either innovative, an overview of a given area, or a very detailed investigation of a small topic. Often the book is not specifically about 2012 features, but practices that can be applied to many versions of SQL Server. Many of the authors suggest ways of working, without mandating it, however they do provide persuasive arguments to back up their approaches.
Owing to the disparate nature of the contents, I'll discuss each chapter in turn. I've given each chapter a rating since it is really like having several types of books within a book. All the chapters are worth reading, but I suspect some of the ratings may reflect my personal interests/bias.
In many ways, this book is a bit like Manning Press's SQL Server MVP Deep Dive books (see side panel and Kay Ewbank's review), which is no bad thing since SQL Server has so many diverse areas of interest.