• by Erik Sass  @eriksass1, April 6, 2010

The pace of deal-making in the online radio arena isn't letting up. This week brings a new partnership between TargetSpot and Cox Media Group, which is joining the online audio ad network.

The deal will give TargetSpot access to streaming audio ad inventory in 82 Web sites maintained by some of Cox Media Group's 86 radio stations, located in 19 markets around the United States. In return, Cox Media Group will be able to offer its online advertising clients the suite of targeting, analytics and performance-tracking capabilities built by TargetSpot over the last few years.

Cox is the latest in a series of radio groups to sign up with online radio ad networks like TargetSpot or competitors like Katz Online Network or Triton.

Over the last year, TargetSpot has signed up Emmis Radio, Tribune Broadcasting, Inner City Broadcast Corporation's ICBC Broadcast Holdings, Lincoln Financial Media, AOL Radio, Entercom and CBS Radio, which owns Last.fm.

Most recently, it signed Harpo Radio, the forthcoming radio platform for media mogul Oprah Winfrey. Katz Online Network signed a deal giving it responsibility for some (but not all) online ad sales for Pandora.

All the online ad networks have also worked to expand their targeting and measurement capabilities. In September 2009, TargetSpot announced the launch of a new proprietary response tracking and reporting system for online radio ads, TargetSpot Analytics. In October, it acquired Ronning Lipset Radio, creating what they said was the country's largest online radio ad network.

Around the same time, Triton bought Ando Media, formerly an independent online radio measurement outfit. Triton's acquisition of Ando came just a month after Ando merged with Spacial Audio, which handles automation and ad insertion for streaming audio for mostly online-only broadcasters.

Triton also acquired Enticent, a loyalty marketer, and merged it with an existing Triton division, Mass2One Media, to form a new unit called Triton Loyalty.