I'm only into Chapter 4 and I have already got my money's worth from the book in regards to information. While it is a very dry read (pun sort of intended), the information in it is fairly easy to understand. There are obvious topics in here that are geared more towards the professional brewer, with topics about brewery wastewater treatment and high end filtration; but the first seven chapters out of 10 will benefit the homebrewer. Many homebrewers are looking for the "how do I" when it comes to water adjustments, but I come from the camp that wants to know why. Without an understanding of why you are doing something, you don't really understand the changes you are making. I have found a lot of resources online tell you how to adjust your water to met specific numbers, but don't really explain the correlation between the changes you are making.
Be warned though, if you are not really looking for a deeper understanding of water and it's influence on brewing. You may be disappointed in the book. The actual "how to" is chapter 7, which in my opinion, from flipping through the chapter, would be worth the money for the book alone. But again, I think you are missing out on the point of the book because there is plenty of "how to" information on the web.
One person on here so far has said this book is not geared towards the homebrewer, and I think that statement is incorrect. This book is just way more than they were probably looking for in regards to information. Only the last 3 chapters are not geared towards the homebrewer. Well, some of chapter 8 may apply but mostly just the first 7 chapters benefit the homebrewer.
With that said, the whole "Brewing Elements Series" from brewer's publications has been very technical so I don't expect anything less.
EDIT: Now that I have finished the book my opinion has not changed. I found the most helpful chapters to be chapters 6 (controlling alkalinity) and 7 (how to adjust water) by far. The only gripe I have is from other reviews around the web about the book being too technical and so on, or wondering why it covers things that homebrewers don't need. The answer is because the book is not geared strictly to the homebrewer. I know we are used to most of the books about brewing that we have access to, to be just for the home brewer. But all of the brewing elements series of books are geared towards both the homebrewer and the pro. So if you are not into the overly technical discussions or the equations, skim them, and focus on the rest. You will still get a lot from this book if you do that.