Twitter says no to ads; So how can site survive?

Biz Stone says the microblogging site will turn to paid tools, services rather than ads

With Twitter Inc. co-founder Biz Stone ruling out advertising on his company's social network, the question for the online business world is this: What will Twitter do to ensure it can survive over the long term?

Stone, in an interview at Reuter's 2009 Technology Summit on Monday (see video), said that Twitter is steering clear of running advertising on its microblogging site but added that it will one day launch new paid tools and services.

Online pundits and bloggers have been closely eyeballing the increasingly popular Web site and criticizing Twitter's lack of a business plan.

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I was just wondering where the income comes from. Wonder how it survived so long without external support.

I don't mind ad as long as it don't interfere with the site experience. I admire Twitter are really putting an effort to try give the best experience to the users.