Blue’s News points to an entry on the Enemy Territory:Quake Wars site (Link) discussing the in-game ads for the upcoming addition to id’s Quake franchise. Here are some clips:

Hi, I’m Neil Postlethwaite, Splash Damage’s Managing Director and one of the Producers on Enemy Territory: QUAKE Wars. I’d like to talk to you today about the in-game advertising we have in ETQW.
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To help cover this level of on-going support without passing the costs on to the gamer, ETQW will feature appropriate advertisements in select locations of our levels. The ads aren’t intrusive and you won’t have to interact with them; they’ll just be part of the normal environment. In fact, there are some places it’s quite odd not to have an advertisement – the sides of container trucks, for example. Great care is being taken to ensure that all our ads are appropriate for the game world and we have absolute approval rights in this area. If it’s not appropriate or it’s distracting, it won’t go in.

The company providing the ad system does not and will not store any personal information or data that otherwise can be used to identify you. All they track is if and how long you look at the advertisements.

Although I’m an old school fan of Quake, I opted out of Quake 4. I was, however, planning on trying ET:QW… mainly to see the game engine in action. Now I’m curious how Splash Damage (with id looking over their shoulder) handles the ads. Another reason to give it a try.