You may recall that we once tackled this important question in the context of e-mail, but now we have a more curious -- perhaps innocent but possibly sinister -- activity known as twittering. Such activity has reenergized social networking, reasserted (once again) the viral hegemony of A-listers like Robert Scoble, provided yet another sandlot for migratory marketers, and even managed to get a guy out of jail on the power of a single word ("arrested").

Recently, I recklessly bumped into Machiavelli on the street while we were both twittering about, well, going across the street. We decided to sit down over Italian roast and biscotti to discuss his acute observations. He's started to carefully analyze and segment all the curious personality types and behaviors emerging from Twitter-land. We agreed to keep a running total at TwitterByMachiavelli.com, but here's the initial cut: