More research (courtesy of eMarketer) on who is using Twitter. By the raw numbers, it's skewing more female than male, and tends to be favored by younger people (66 percent are 25 or younger).
Ok, that's who's signed up. But the fact is most Twitter users -- more than 85 percent -- post Tweets less than once a day. From there, the numbers go down significantly -- until you get to 10 times per day, when they go up again. According to eMarketer, "This means a small group of users dominate the Twitter timeline—75% of all Twitter activity comes from just 5% of users." From what I see, a lot of that is marketers and alleged social media experts telling each other how cool Twitter is.
It's certainly a technology to watch, and there are some success stories. But it will be interesting to see how Twitter shakes out in the long term.