Despite the zillions of startups trying to get a piece of the mobile social networking pie, MySpace leads the pack anyway with 3.7 million monthly users in July, according to M:Metrics.

Not only that, but Online Media Daily reports that Facebook placed second, with 2 million, while YouTube rounded out the top three with just over 900,000. In other words, the top three are the same familiar names you'd see on the desktop.

Still, while the numbers are impressive, they represent a tiny slice of the wireless market. "The mobile media measurement company, in its first report from a study of social networking via mobile phones, found that although some 7.5 million Americans accessed mobile social networking sites last month, they accounted for only 3.5% of all mobile subscribers," said the report.

"Nearly every online social networking site has added the ability to connect to these communities with a mobile phone," said M:Metrics senior analyst Mark Donovan in the article. "With the mobile phone playing a central role in people's social lives, it's only natural that social networking sites are working to bridge the gap between the online and mobile worlds."

MySpace Leads U.S. Mobile Social Networking [Online Media Daily]