This book exceeded my expectations. While the primary title is distracting and somewhat misleading, the subtitle gets it right.
What struck me about many of the profiles were the incredibly useful details disclosed by some of the vendors. Sure, a few vendors are basically boasting and (I suspect) exaggerating their returns, and some are conspicuous in failing to share information that some others disclosed (such as net advertising revenues).
I actually think this book should be on the "required reading" list for anyone starting a web-based business, simply because it highlights some of the key issues and reasons why some of these businesses are successful (and by implication, this should give some clever people good insight or warning as to why some other business ideas are lacking).
My only hesitation about the book is that since it only profiles successful businesses, including some that are in very narrow niches, it may lead some new web-based business owners to be overly optimistic about their new projects. For example, the first "niche" site profiled in the book reports earning $330 CPM for its advertising (and the book explains why this is).
A little "reading between the lines" does help (start by simply noticing what information is included in some profiles but not others, and imagine why one vendor didn't share their information). Also note that some of the "successes" seemed (to me, at least) to be more likely than not to be short-lived.
The book is also a "good read" -- ideal for an airplane trip or relaxed weekend reading; each of the 23 profiles can be read completely independent of the others (in any order, so you can start by reading about the web sites that are most similar to your business, and then move on to gain insight from other businesses that seem completely different). I don't recommend the book as bedtime reading, because even if you want to just read one chapter, you'll probably be unable to resist reading another profile, and another -- plus your brain will begin grinding with new ideas as you read, making it harder to get to sleep.