For several months, Google has apparently been running geo-targeted contextual ads in RSS feeds without having expressly said so, and online documentation for AdWords doesn't mention ads being distributed to feeds, referring only to their showing up on content sites and "products," reports ClickZ. "I don't think most advertisers know it's going on," said Kevin Amos, director of product management at search marketing firm Impaqt.

Shuman Ghosemajumder, business product manager at Google, told ClickZ that geo-targeted feed distribution has been part of "AdSense for feeds" since its launch in May 2005: "AdSense for feeds is part of the Google content network, so if an advertiser's campaign is opted into the content network, their ads are eligible to show in feeds."

Advertisers cannot directly geo-target RSS ads, but targeted ads in Google's content network could end up in feeds. Both user location and feed content are targeting factors, with the latter as the primary factor.