I was skeptical of this book, and put off reading for sometime. My reason was that although acquisition and penetration seems to be at the core of the message, as big brands having a slight edge on retention than smaller ones (I saw some youtube's by professor Sharp), the book is not available in Kindle. Anybody writing a book and really wanting to acquire bunch of new audience probably shouldn't say no to a channel that controls 70-80% of the e-reader market. I tweeted to prof Sharp and he had his reasons, mostly centered around the formatting of the book being harder on Kindle, which might be the case ( Although I believe Amazon is way too advanced for not formatting charts and tables correctly, and I have self published my daughters poems, it was very easy).Moving on beyond why I didn't read the book early on. I think this book is absolutely fantastic read. It is written in a matter of fact way, with data points for every argument it makes. It was recommended by Dr. Fader (Wharton School) , after I asked him a certain question, and I had to change my mind and actually read it. He was spot on. Lot of the findings in the book are very close to what I have seen in practical data. If you are in midst of digital advertising revolution and working on a relatively smaller brand this book will clear your head on some misconceptions or lets say popular notions of brand building and may give you new ideas on how to go about it. I rather not summarize the book in my review, but I think the book gives the reader different ideas on the few questions such as retention vs acquisition, understanding the relation ship of cross selling to customer base, how much to sweat on retention and defection, focusing and trying to acquire a certain customer segment relative to brand size.In short, I would say whether you agree with the book or not, it is a must read.