Michael Arrington provided a more likely story by writing this afternoon, Dick Costolo is Twitters new chief operating officer, weve heard from multiple sources.

. . . Wed heard he was looking to start a new company, but obviously Twitter swooped in and grabbed him.Since hes worked for both a startup and a corporate giant with a 144 billion market cap, Costolo may be in a good position to help Twitter mature as a business. Experience on both ends of that scale is hard to come by and often quite valuable.If and this is an if that at least a few people are thinking about Google tries to buy Twitter, Costolo could probably help there, too.