Twitter — which has raised $55 million so far — is now looking to raise an additional $50 million at a $1 billion valuation, TechCrunch reports, citing comments that were made at a company-wide meeting. Twitter last raised money in February — when it got $35 million in a third round, which valued the company at $250 million. Since then, Twitter’s popularity has soared; Compete figures show that the number of unique visitors to the site has more than tripled since February.
Of course, Twitter still isn’t monetizing any of its users, although it’s finally taking some steps to do so. It changed its terms of service last week so that it could target ads, and it has said that it will soon start charging for premium accounts. While revenue is basically nil now, earlier this year it said it expected revenue to reach $140 million by the end of 2010, which makes the valuation seem more reasonable.
We’ve reached out to Twitter for comment and will update if we hear back.