I've been playing with Twitter of late (you can find me there at FredatDreamtime if you're interested) and have been going up the "what is this good for except as a major productivity buster?" to the slow dawning of awareness scale that apparently all Twitter users go through.
Is Twitter useful for someone like me remains to be seen, but in some cases and for some people it is useful to create dialogs with your audience. Here's an example - Roger McGuinn, yes that Roger McGuinn, twitters. And if you had been following him last night you would have found that Bruce Springsteen invited him backstage at his concert last night, and the two ended up on-stage doing Turn, Turn, Turn.
And yes, the video is exceptionally wretched. But think a second. Here I am sitting in New Hampshire, reading notes from a rock star in almost real time, and then watching a video of what he's talking about a few hours later.
In some ways we really are living in the future.