According to the Twitter blog, Twitter users were tweeting 5,000 times a day in 2007. By 2008, that number was 300,000, and by 2009 it had grown to 2.5 million per day. As of January 2010, the company is seeing 50 million tweets per day—that’s an average of 600 tweets per second.
And the counts do not include spam.



[...] They further analyzed the content of 1,000 tweets to see what the content was and found that 30% of tweets relate to a user’s “status” (what they’re currently doing or where they are), and 27% were private conversations. 10% contained links to articles. 4% of tweets analyzed included product recommendations or complaints — a small percentage but a huge amount of data if you consider that Twitter is now logging more than 50 million tweets a day. [...]