Dave Moore, whose interview with William F. Buckley Jnr is well worth a look, has a characteristically trenchant but winsome article about omerta over at Two Cities.

A taster: "I have been around many leaders.  Some I've worked with, some I've interviewed, and some are friends.  All are human, yet the ones willing to speak tough truths, especially within their own organizations or companies, is sadly too small."