Lots of cool Twitter statistics coming out of Barracuda Networks new study (pdf).

Where do I start?

• 21% of Twitter users are actually using the service–meaning that have at least 10 followers, follow at least 10 people, and have tweeted at least 10 times.
• 74% of Twitter users have less than 10 followers! However, that number is improving with a 30% increase in the number of users with 10+ followers (since June 2009)
• 60% of Twitter users follow less than 10 people
• 34% of Twitter users have more followers than others they are following, showing an 70% increase from 20% in June 2009
• 73% of users have less than 10 tweets, as compared to 79% in June 2009.
• 49% of Twitter users joined between November 2008 and April 2009–the period when many celebrities jumped on the Twitter bandwagon
• Twitter’s growth spiked at 21% in April 2009

Lastly, who tweets the most? Those with around 1,000 followers do:

I’m guessing that’s the sweet spot of actually being able to engage and keep-up with your followers.

(via)