I think the book challenges the definition of "rich" kind of like how MMM challenges the definition of "retired". Until a few years ago, rich to me was, as someone said above, "Hollywood Rich": exotic cars, big fancy house, country club memberships, designer clothes, exclusive private schools, etc. I suspect that this perception is not uncommon. In fact, one of my close friends recently said, "...the guy must be rich, he drives a brand new BMW, has nice clothes..."
In general, I enjoyed the book, although, I'd like to see more profiles of different types of people. I already know and understand the message of the book---I knew it before I read it. But, personally, I really enjoy Reader Case Studies here on MMM; I'd like to see a whole book filled with profiles. I just find it interesting to read about how other people live.