The direction we're going in, where our friends can present challenges to us in the middle of what is otherwise a straight-up single person adventure, is going to turn out very well, I think. First Resident Evil 6 gives us Agent Hunt mode where we can hop in to a buddy's game as one zombie among many and now Hitman Absolution is giving us Contracts Mode where we can label any character in the game as a target for others to take down.
Simply put, you'll be playing Hitman and decide "Hey, I want that guy with the mullet to be dead, but I don't feel like doing it myself right now because I'm busy hunting sexy nuns in leather." You can tag that mullet dude, put a contract on his head and other Hitman players around the world can kill him to much celebration and reward. It's like quickly building a wrinkle into a mission with its own parameters, conditions and rewards. Cool concept.
Watch the trailer and start thinking about ways to make this challenging for your buddies.