After reading countless books and information on websites based on game engine design and architecture, this, to me, is the definitive book written by a professional, for beginners, hobbyists and other professionals alike. The way the author seems to seamlessly blend information that is useful to the less experienced and information that is crucial to all is possibly the best I've seen in any computer book, let alone one of the game development genre (of which I own dozens).
If you're even remotely interested in game engine architecture, or games in general, or even large-scale modular c++ systems, this is a compelling, if almost unputdownable, read. If you're an experienced developer and are looking to get into games or game engines and understand the finer details but not how engines pull everything together, this will answer practically everything.
One of its best attributes is that you don't have to trawl through endless pages of dreary engine code. There are snippets of code in the book, but they are snipped and presented in context and in such a readable fashion that they seem to blend into the prose and most definitely add just enough splashes of technical colour. A lot of books on engine architecture seem to concentrate more on coding the individual components, with little time spent on how everything fits together. The author has worked on AAA titles and gives regular insights into how things were done on those titles.
Most of the computer books I've read, especially in the game genre, have me searching for the author's email address to ask for clarification on certain areas. This author seems to have the nack of explaining things perfectly.
If you're about to invest in some literature about game engine architecture (this isn't a cheap book, hence the use of the word 'invest'), my advice would be to have a look at this one first.