If microblogging service Twitter was entertaining even the slightest notion of charging for its service, then it might want to reconsider. A recent survey of nearly 2,000 people found that zero percent – you heard correct – of respondents would pay to use the service.

The survey, conducted by the University of Southern California’s Annenberg School for Communication and Journalism, is part of its yearly “Digital Future” report, which looks at the overall state of the Internet in the U.S., from adoption to views on advertising and paywalls.

Jeffrey Cole, director of the Center for the Digital Future, said that the response shows just how difficult it can be to begin charging users for services and goods they already receive for free.

“Twitter has no plans to charge its users, but this result illustrates, beyond any doubt, the

tremendous problem of transforming free users into paying users,” said Cole. “Online providers face major challenges to get customers to pay for services they now receive for free.”

Of the survey’s 1,981 respondents, 49% had “used free micro-blogs such as Twitter.” While 70% said that they found Internet advertising annoying, it was by far the most preferable outcome (outside of completely free, ad-free content), with 55% of respondents saying they “would rather see Web advertising than pay for content.”

As PaidContent’s Joseph Tartakoff notes, Twitter has never said it has any plans to charge for the service, lest we start any rumors.

While the survey came up with nobody saying they would pay for the service, we have to imagine it was just missing the proper segment of the population. Our own reader poll (last year, at that) found that 20% said they would pay under $5 a month to use the service, while 66% said they would pay nothing. As for our own Marshall Kirkpatrick? He said that he would easily pay $50 per month for what he gets out of Twitter for a number of reasons.

How about you? Would you pay for Twitter? Why or why not?