The good news: a new study from the Pew Research Center shows that over a third of Twitter users read other users' tweets at least once a day.
The bad news: nearly 50% of Twitter users do not look at other users' content more than once a week. In fact, 20% only browse other people's tweets every couple months, and 21% never read them at all!
Not a good sign if you're trying to position yourself as a revolutionary communications medium. Then again, I'm not surprised at all.