europeforvisitors - 6:51 pm on Feb 3, 2006 (gmt 0)

Heck, there might even be simple "run-of-network" campaigns, which are the antithesis of what AdSense was originally conceived as.

That's probably what they are in most cases. Still, RON "rich media" ads might work better than contextual ads on a lot of general-interest sites (news sites, for example, where there aren't a whole lot of good contextual ads for articles about roadside bombs in Iraq, political corruption in Washington, or physician-assisted suicide in Oregon).