Shares are up 14% in late afternoon trading and touched an all-time high of $32.45 today after Pandora unveiled surprisingly strong audience results for December — and a plan to introduce in-car advertising. Pandora_logoThe streaming music company had 76.2M active listeners in the month, up from 67.1M a year ago, and accounted for 8.6% of U.S. radio listening, up from 7.6% last year. The results “once again demonstrate the resilience of the service in the face of iTunes Radio competition [which launched in September] and Spotify,” says Cowen and Co. analyst John Blackledge. The company also announced at the International CES confab that this month it will harness users’ smartphone connections to introduce in-car ads for companies including BP, Ford, State Farm, and Taco Bell. “Nearly half of all radio listening takes place in the car,” says Chief Marketing Officer Simon Fleming-Wood. “We knew early on that to redefine radio, we would need to seamlessly deliver Pandora through in-dash entertainment systems.” The service says it can offer “a more targeted audience than traditional radio can provide” by providing 15- and 30-second ads to “car-bound audiences” via more than 270 devices that offer Pandora in cars. The company says that it will pump fewer ads to drivers and passengers and it does to Pandora users on other platforms — except those who subscribe to the ad-free Pandora One premium service. Wedbush Securities’ Michael Pachter says that while the auto ads present “a differentiating and compelling opportunity” for Pandora, he’ll reserve judgment until he learns “additional financial details about the service.”

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