Much has been made of Twitter’s current lack of a business model; we’ve even highlighted the fact that third-parties like Glam Media have found ways to make money from the free micro-blogging service, while it continues to accrue users and publicity, but no revenues. But outsiders can speculate about Twitter’s business model all they want, according to Spark Capital founder Todd Dagres, who told Innovation Economy that the startup definitely has one—and that it will be easier to implement than naysayers might think: “All of a sudden there will be some changes that won’t undermine the experience or the virality ... We’re very confident about how we’re going to do it, and it’s not necessarily in our interest to tell people how we’re going to do it.”

Dagres’ Boston-based VC firm led Twitter’s $15 million second round last year. He has experience with a number of successful new-media startups, as Spark Capital has backed lonelygirl15 studio EQAL, Obama Girl producer Next New Networks and digital media browser Boxee. He told Innovation Economy that while getting Twitter to generate revenue was a major focus for 2009, there was “no rush,” echoing co-founder Biz Stone’s statements that the startup was sitting on enough capital to remain comfortable. Still, he did acknowledge that the money-making plan ultimately might not be successful: “Of course, I can’t guarantee it’s going to work.”

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