How does the Xperia Play work? I mean in terms of multiplayer gaming. Can you play against only other Xperia Play phones? Can you play against PSP devices? Can you play against any Android phone? And/or does any of this depend on the game? For instance, if it's an Android game you can play against Xperia Play users and any Android device? Or if it's a Sony game can you play only against Xperia Play users only or can you also play against PSP users?