It's a better than average mob book, though, as it was co-written with Hillel Levin, the former editor of Chicago Magazine, so it isn't just some schlep recording every whopper that a turncoat tells him and writing it down. It was all treated with good journalistic practices etc. And I think the vast majority of it was verified off the wires Cooley was wearing.
I actually agree on the overall quality of the book. Cooley has repeated something very interesting more than once in interviews: That, as far as he could tell and to the best of his understanding, Pat Marcy was the most powerful figure in the Outfit (more so than any other single individual, boss or not) in all his years of being affiliated with the Outfit. That is a pretty powerful statement from someone so well-networked at the time.
http://www.youtube.com/watch?v=ofs3-rxmCpM
