It's mostly about gossip, the subject of two of the book's chapters. To go to the source for a lot of what's in the article, check out the work of Ronald Burt at U Chicago. He's found that one's reputation is a product of one's social network, and that the kind of reputation you get depends a lot on the structure of your network - particularly on how closed (cliquey, in which everyone talks to everyone else) or open it is.
In particular, I refer you to these two pdfs:
Closure and Stability: Persistent Reputation and Enduring Relations among Bankers and Analysts
And his 2005 book Brokerage and Closure.
