First let me state that you cannot learn wing chun from a book, you really need a qualified instructor and you must test ideas continually. That being said, this book is fabulous as reference material which seems to be exactly what it was supposed to be. It has the common terms listed in English, Cantonese and Mandarin as well as key to pronunciation.
It is laid out very simply and concise, much like the art itself. It covers the core principles of the system and it does a good job of explaining chinese ideas in english. It has a pretty in-depth explaination of meridians (channels of chi) that would appeal to anyone trying to understand the difference between chinese and western thinking on the human body.
It does about as good as is possible in a book at describing the art itself, which means it beats anything I've seen previous. Little philosophy quotes/ideas are listed throughout the book along each page...a very nice touch. It allows a mix of the philosophy into the work without making the direct content become too flowery. It stays on topic and is very efficient at describing the system.
I'm sure various wing chun students will have minor changes in the forms and such, but overall the work is invaluable to students of the system. This means it doesn't try to be a learning manual for the untrained but more a reference book for those that do. Instead of listing the specifics of one lineage it sticks to the core ideas which is a challenge that most books seem to fail on. A lot of MA books focus on trying to sell as the new and best "secret" system to overcome all other fighting arts...this one does not. The author achieved his goal of providing a thorough, accurate reference text on Wing Chun. The tone is rather neutral in that it avoids politics and presents the material without trying to over-prove it's validity. It's very "here is the theory, this is what backs it up, these are some examples of theory in practice, here is reference material for further study".
It may literally be the best martial arts book I've ever seen.
The author has gone to alot of effort to write this book. This books covers all the empty hand forms with great detail. This a great reference book for wing chun. Highly recommended.