• by Mark Walsh  @markfwal, June 28, 2007

For a century-old medium, radio sure is getting hot. Online giant eBay last month said it will let advertisers and agencies bid for radio advertising time through its Media Marketplace on most of the country’s stations. That puts eBay in direct competition with Google, whose AdWords for radio initiative also seeks to create an automated ad system for radio.

Google most recently partnered with Clear Channel Radio to sell a guaranteed portion of 30-second advertising inventory on over 675 radio stations. Google Audio Ads can target specific geographics and time slots.

Ebay is looking for better success than it’s had brokering TV advertising on its Media Marketplace that it launched last year. It has met with stiff resistance from major TV networks, despite support from big advertisers. Oxygen recently became the first cable network to make ad inventory available on the eBay exchange in defiance of a Cabletelevision Advertising Bureau-led boycott of Media Marketplace.

To help smooth its path into radio, eBay is teaming with Bid4Spots.com, a media auction site specializing in broadcast inventory. The new radio auction system will include inventory of most top-ranked stations, including those owned by Clear Channel.