ArmA 2 is much more exciting that MW campaigns.

/sarcasm

But on a slightly more/less serious note, it seems the genre is in a rut when it comes to a campaign in war-games, I think the reason that CoD is all the same is because Activision is forcing a new game every 6 months, which just isn't good enough, the devs don't have time to come up with decent ideas or even make anything more innovative, because it's a 'risk' and not 'profitable' to Captain Kotick, Commander of the Dickship.