The number of consumers worldwide using their mobile phones to access social networks will more than triple from 2010 to 2012, according to Pyramid Research's "Social Networking Goes Mobile" report.

Mobile social networking has been hit-and-miss in the US so far. Mobile carrier Helio positioned itself in part as the best network for MySpace users—or at least one of the first. On the verge of bankruptcy, the company got a reprieve last year thanks to a sizable investment by South Korean carrier SK Telecom.

Despite that high-profile stumble, AT&T continues to offer a paid version of MySpace Mobile, while MySpace itself offers a free mobile version of the site.

The demand for these services, while not necessarily universal, is strong among some specific geographic and demographic groups.

Mobile social networking demand is high among UK mobile users, more than one-quarter of whom said they desired the service, according to a January 2008 Webcredible study. That was second only to their desire for mobile e-mail.

US teens are also primed for mobile social networking, according to data from the Pew Internet & American Life Project released in December 2007. Nearly 500 social network-using respondents in that study said that mobile phones were their main means of daily communication.

That would appear to make social networking by mobile phone a sure hit for US teens.

Teen interest in Facebooking or MySpacing by phone will likely grow through at least 2011, when, eMarketer predicts, more than eight out of 10 online teens will be social networking.

Whether or not that demand will result in the threefold worldwide increase in mobile social networkers predicted by Pyramid is still an open question. Enough demand exists for sustained usage. The question is whether users will remain a healthy subsegment of the market, or become a mass market in themselves.

"Mobile social networks, like their Internet counterparts, face the challenge of bridging consumer demand with a business model that can scale appropriately," said John du Pre Gauntt, senior analyst at eMarketer. "Content and service subscriptions in mobile often hit a wall much sooner than their business plans call for. Advertising requires a level of scale and targeting sophistication that isn't there yet."

"What this suggests to marketers is that consumer demand is necessary but not sufficient to make mobile social networks a must-buy in 2008," Mr. Gauntt said. "It's still experimental."

The eMarketer US Mobile Advertising and Marketing report will be published this month. Click here to be notified when it is released.