We have seen small glimpses of this with Shadowrun (X360/PC) and Portal 2 (PC/PS3), but could you imagine being able to play Madden, Nba 2k12, Modern Warfare 3 or Goldeneye: Reloaded with your friends on another console? This would totally up the cool factor on any multiplayer game. Bragging rights would cross console lines. Heck, they could even offer achievements for dominating players on other systems.
Sadly, there’s a lot of red tape here. Nintendo doesn’t really have an online platform, Sony’s is open (but a joke), and Microsoft has closed Xbox Live tighter than Fort Knox.
Even less promising still is the fact that the new Nintendo console may be powered by Origin (EA’s online rival to Steam). Sony is in bed with Steam, so that pretty much kills WiiU/PS4 interaction. Finally, I don’t see Microsoft budging from their isolationism any time soon.