But Fry wasn’t being deadly serious, and Stone is content persevering with Twitter’s cautious, softly-softly monetisation plans. He said plans to start selling corporate accounts, first hinted at in August, are on-course. A pay-for package offering verified streams and an analytics package will be available by year’s end, he said.

“This takes advantage of some of the commercial use of Twitter we’ve seen from businesses like airlines and big box stores… we want to present to them a layer of features that allows them to become better at Twitter, show them some of the analytics.”

Fry, whose own popularity has skyrocketed still further on the back of his tweets, is now closely associated with the service. With that, comes an appreciation for Stone’s monetisation issue. Fry added: “He knows that, if Twitter became annoying to users with flashing banners and there was a sense it was being guided by a big corporate brother, (users) would go off and found their own.”

—Competition for Twitter?: “There are other companies inspired by what Twitter is doing and I think that’s great… We’re seeking to release our data and form partnerships.” Quoting Google (NSDQ: GOOG) CEO Eric Schmidt speaking about search competitors at an in-house Google meeting years ago, he says: “We should look in the rear view mirror, but if we stare in the rear view mirror we’re going to drive right off the road.”

—What future direction?: His colleagues have said it before, but he’ll say it again: Stone very much sees Twitter’s future in mobile: “When we look at where we can grow we look to the more than four billion active mobile phone accounts in the world, opposed to the 1.65 million active web accounts.”

—The future of media?: As Twitter grows its users, reader and viewers are straying from TV news and newspapers—can Stone help their plight? He says he can: “As we begin to add thing such as the ability to geo-tag an individual tweet and recognise which users have higher reputations than others, that will feed into the culture of news organisations.”

—Grand ambitions?: When Stone says Twitter’s changing the world through mass social interaction, he really means it: asked how he wants the service to be remembered, he says hopefully it will be “not as a triumph of technology but a triumph of humanity”.