I hope they incorporate multiplayer games that are independent of the main game, complete with their own gameplay. The reason I say this is because in most games where the multiplayer isn't part of the core-experience (e.g. an adventure game), the gameplay feels often unnatural and forced, and becomes repetitive very quickly (of course there are exceptions).
An example of a game that did it right in my opinion is Super Monkey Ball. Those multiplayer games had nothing to do with the main game and therefore the developers were free to come up with unique and solid gameplay elements for multiplayer, instead of gameplay forced into them from the main game. The multiplayer games were: Monkey Bowling, Monkey Target, Monkey Golf, Monkey Billiards, Monkey Race, and Monkey Fight. All really solid 1-4 player games that were a ton of fun to play, because they were specifically made for multiplayer.