Anywho while this "bump" is still somewhat fresh (Yeah right!) it might be good to discuss a little more on the subject.
From what I read last year there would be scenarios where you would have to deal with waves of Xenomorphs, however not entirely like Survival in the
AvP games where you're running around looking for Aliens to shoot and its basically endless. You have to basically hold your line until the xenos stop and look for alternatives. In order to hold them off, you are given sentry guns to set up, Weld torch to weld doors shut, and of course you're motion trackers to help know which way they're coming from.
Now some things that would interest me is that when less xenomorphs start focusing on getting the drop on you, you get your squad and take a less infested route to escape and of course take a breather. You won't have enough ammo to kill every single one so take advantage of flight so you can survive a little longer. Also finding the bodies of some of the previous Colonial Marines would be pretty cool (Not like Hicks, Gorman, Vazquez, and Drake. But Hudson, Apone, and Frost, to name a few). Plus finding their weapons for extra ammo helps.