In a yanked interview with GGL Wire, actor Brad Hawkins has revealed that DOOM 4 is to feature distinct civilian and military groups.
“‘[Filmmaker Mark Bristol] was very specific on the civilians having a certain personality and the military characters having a separate one as well. The body language of the civilians is less, well, “trained.” They carry their guns in a looser fashion and are a little sloppier when they run, a little more freestyle. The military characters are sharp as razors, with very swift moves, exact hand positioning and can turn on a dime.’”
This is the summary total of everything known about the game so far. Don’t hide it, id. You can’t beat the internet.