Twitter Mainstream? Not Yet

"A source close" to Twitter provides TechCrunch with what is supposedly the first realistic assessment of Twitter usage stats. Conclusion: It's a lot more popular than it used to be, but still confined to a tiny swath of early adopters:

March 2008
Total Users: 1+ million*
Total Active Users: 200,000 per week
Total Twitter Messages: 3 million/day

Assuming these stats are accurate, or reasonably close, they're much more useful than the numbers from Hitwise, Compete or Comscore, which track visitors and visits to Twitter's site itself: We've heard that as much as 70% of Twitter usage happens away from the site, either on mobile phones or via one of the many Twitter apps.

The good news for Twitter as it tries to raise a C round: Its March stats show considerable growth: There were supposedly 50,000 active weekly users in in April 2007, and 100,000 in January. The less good news: It's still a niche service, and one without an obvious business model.

Update: Our own source close to Twitter tells us that as of three weeks ago, the service was up to 1.3 million users, with nearly 4 million "connections" -- Twitterers following each other. It's that second stat that speaks volumes about Twitters' appeal to its users.

See Also: Twitter Raising Money; How Much Is It Worth?