So, Multiplayer campaign as we know it ( aka Split-screen co-op ) really isn't possible at this stage.
But what about other means by which to make campaign more friendly to multiple players? I don't know about you, But I'm probably going to be playing some campaign with friends regardless, But some accommodation sure could make it a heck of a lot more fun.
Even something simple toe in, like switching out with another player when you die, instead of using checkpoints could be way fun. Especially single player has user customization for your character and guns. And then of course, at the end of each level it would show each players stats side by side, and declare one a winner.
And another multiplayer related thing... Why don't any FPS's have unlockable mini games or anything? Do they think they're too cool?
I wouldn't say no to a minigame or two. You know, every year my whole family gets together on christmas and plays the mini games on diddy kong racing. Every Year, for 12 years! And we also play kirby mini games.
Strange that Goldeneye, super smash, etc. The big multiplayer games in other words, get neglected in comparison to a small collection of simple games that are just fun to play.