Piracy exists, and there is nothing anyone can do to ompletely stop it without seriously pissing off consumers. You know what annoys me? When the pirated version is superior to the purchased copy like in the PC version of Modern Warfare 2 or any heavily DRM filled game. The best way to combat piracy is to ensure the customer perceives that they get great value and service from a purchase over a pirated copy. Community programs like Steam and Live (with the banning) won't stop piracy, but they can help reduce it. Alternatively, you could use advanced or proprietary technology like Blu Ray in PS3 where piracy just isn't economically feasible or worth it (but this of course is more expensive for the platform holder).
Have to say I'm suprised by the sheer number of downloads for Wii and 360 games, I had no idea that console piracy was THAT high.