<http://schema.org/description>
"Twitter has just surpassed the 10 Billion tweet mark.\r\n\r\nAccording to GigaTweet, a tweet-tracking service, Twitter's 10 Billionth tweet was tweeted at 6:54 PM US Central Standard time. ..."^^<http://www.w3.org/2001/XMLSchema#string>
<http://thenextweb.com/socialmedia/2010/03/05/twitter-surpasses-10-billion-tweets/>