Google announced it will begin accepting third-party advertising tags on the Google content network (Adsense) in North America. This will enable advertisers to work with approved third parties (see below) to server and track display ads, including rich media ads.

Third-party tags were not accepted in the past as Google dis not have a process for reviewing ads to make sure they complied with their format standards and policies. Now that that's in place, Ad servers, rich media ad agencies and resarhc firms can go through a certification process that ensures the highest level of advertiser service and user experience. Advertisers and agencies now have the ability to serve ads and measure performance through these certified third parties (more will be certified in the future):

Advertiser ad servers: DoubleClick (DFA), Mediaplex
Rich media agencies: DoubleClick Rich Media, Eyeblaster, EyeWonder, Interpolls, PointRoll, Unicast
Research firms: Dynamic Logic, IAG Research, InsightExpress, Factor TG