I just received my copy. It's great, over 300 pages full of information and everything you need to know about brackish fish. It covers everything, even with a section on coldwater brackish and marine aquaria. The Mudskipper chapter I found especially useful and it is written by Richard Mleczko (from Richards Mudskippers). I was also astonished at the sheer number of fish available which can be kept in Brackish water conditions. Basically, if you want to keep a brackish water aquarium of any type, buy this book, I strongly recommend it. I also have the Aqualog book by Frank Schafer, this book only has about 70 pages and only has brief descriptions for really the most commonly traded species. Unlike Neale Monks' book it doesn't cover a wide range of species, such as low-end brackish fish to high-end to marine brackish fish. If you post quite a few topics on this Brackish forum, then I would suggest you get this book.
Cheers,
Mike