My overall rating is: Meh
I did learn a lot about Mr. Buffett, but I felt like the book failed to commit. Was it about his life? Or was it about business? True his life and business are so tightly intertwined as to be inseparable, but I thought the book failed to delve deeply into either.
For example while his personal life is both interesting and unorthodox this book gives only an arms length view. Even after 900+ pages I still can't say that I fully understand the real dynamics of the most important relationships in his life. Business adventures are covered, but not at the level of detail you'd need to get into the mind of the master, it's there as part of the narrative.
So if you're a diehard Buffett fan like me, get the book and enjoy. However if you're not hardcore, it's safe to pass.