I vote for dynamic campaign BUT what I really want is a dynamic CO-OP campaign that can be scaled from single player to multiplayer CO-OP with various number of players.
In addition to that (I know I am asking too much), I hope that there is a built-in multiplayer online interactive mission planner so that we can easily plan on how to do a co-op mission (at least let us plot waypoints) without using 3rd party tools.