Twitter Chief Revenue Officer: As of November 2011, Twitter has 2,400 advertisers

On December 1, 2011, Twitter Chief Revenue Officer Adam Bain revealed that Twitter currently has 2,400 advertisers.

He declined to reveal the revenue composition, but said Audi, Paramount and Volkswagen used promoted tweets, promoted trends and promoted accounts for advertising.

"You only have 140 characters to do your marketing, but you can do a lot in those 140 characters," Bain said.

Market research firm eMarketer predicts that Twitter's advertising revenue will reach $139.5 million in 2011, a 210% increase from $45 million in 2010, and that advertising revenue will increase 86.3% year-on-year to $260 million in 2012.

Bain also confirmed that Twitter has more than 800 employees.