As I went through this book, the word that kept creeping to mind was: Wow! This book is incredibly rich. One thing I know working in the information architecture/experience design field for so long is that it's all about "connecting the dots" - but first you have to know what the dots are. This book, while written from a designer perspective, brings all the relevant dots to the surface and connects them for you. It does a fantastic job of setting the cognitive contexts for concepts and defining terms in a clear way. Another thing that struck me about this book is its own information design: this book practices what it preaches from a communication perspective.
The reason most companies hire me into a Creative Department is to bring the type of consciousness to a project that this book embodies. This book educates, not just designers, but everyone on the team. It's very nearly a complete compilation of best practices to date, worthy of a classroom textbook.