• 72.5% of all users have joined since January 2009
• 85.3% of all Twitter users post less than one update per day
• 21% of users have never posted a Tweet
• 93.6% of users have less than 100 followers, while 92.4% follow less than 100 people.
• 5% of Twitter users account for 75% of all activity
• New York has the most Twitters users, followed by Los Angeles, Toronto, San Francisco and Boston; while
• Detroit was the fast-growing city over the first five months of 2009
• More than 50% of all updates are published using tools, mobile and Web-based, other than Twitter.com.
• TweetDeck is the most popular non-Twitter.com tool with 19.7% market share.
• There are more women on Twitter (53%) than men (47%)
• Of the people who identify themselves as marketers, 15% follow more than 2,000 people. This compares with 0.29% of overall Twitter users who follow more than 2,000 people

Interesting facts about Twitter‘s current user base, perhaps it will look much different in 6 months.