It did happen : at the Casual Connect conference, Google representatives Bernie Stolar and Greg Schaffer said that the company was about to launch AdSense for Games, an AdSense contextual advertising service for online games. In the future we plan to expand the service to console and desktop games. As usual, advertisers will get access to the new service through a single AdWords interface.
Bernie Stolar said that Google is not going to develop its own games. The official launch date for AdSense for Games is not yet indicated.