CBS has partnered with social network Loopt for a geo-targeted mobile campaign, reports Advertising Age.

The campaign serves Loopt subscribers ads specific to their current location when they visit mobile CBS News, Sportsline or Marketwatch sites. Subscribers must activate the locater feature on their handsets to receive the ads.

That users must switch on a feature to share their location should ease privacy concerns. Only banner ads will be served, as opposed to unwanted text messages or other forms of mobile advertising that may be perceived as intrusive.

Loopt is currently available on Boost Mobile, Sprint and select Verizon Wireless handsets. The company hopes to line up more partners soon.

The CBS/Loopt program conducted beta testing through Q4 of 2007.