It seems that the Xbox 360 is the gamer's choice for online gaming. Recent data from the NPD Group says that the Xbox 360 sold roughly twice as many online-capable games as the PS3 in 2010. And the Wii? No contest. Microsoft's console sold seven times as many online-capable games as the Wii. The data does not detail how frequently these games were played online, but I'm sure it's safe to assume that the Xbox 360 would come out on top in online usage.
The Xbox 360 also comes out on top when it comes to retail point cards. According to Gamasutra, retailers sold nearly four times as many Xbox 360 digital points cards than PS3 cards in 2010. Graphs show that the Xbox 360 has always been on top for both game cards and online software, from 2006 through today.
It's probably going to stay that way for a long time.