This book is very well written and follows a fine balance between theory and practical applications. Not a cookbook with receipees but a solid foundation for understanding and designing solutions.
I find the book slightly leaning towards large spaces (auditoriums) and diffusers while my main interest lies in small - listening - room treatment where absorbers tend to be more useful. However the book contains extensive and probably complete coverage both on diffusers and absorbers.
One "bonus" part of the content is measurement techniques. Unless some solid method for measurement is available, one can't really discern between a good solution and a mediocre one or a failure.
This is a book one expects to read several times. As experience builds up, each new reading is going in more depth and some of the chapters I glanced through on first pass became apparent and useful.