This book was only sort of what I was expecting. I would have liked a lot more detail on how governments and private groups are successfully rewilding areas in the UK, Europe and the US, since those seemed to be the author's main frames of reference. The author eventually got into the heart of the subject matter about 3 or 4 chapters into the book; the first several chapters really don't go anywhere, so it's a very slow start.
Overall it was still interesting and pretty good. I definitely agree that more wilderness needs to exist in the world, both on land and in the seas, so it was kind of preaching to the choir.