[…] It’s easy to tell the difference: The guy on stage at the concert is in front of his audience. The people in the stands are in their community. When the concert is over the audience vanishes but the community continues; with or without the man on stage.
The stage metaphor is a bit strained, but this is similar to my own philosophy on Twitter and other social media sites. Unless you have millions of followers, treating Twitter like a broadcast medium means you miss most of what it’s good for.