As long as we still have Sigourney .. we'll be OK.
The question is, would they really be like the ones from "Aliens"? My guess they wouldn't be much different from us in terms of, they would most likely need to have arms and legs to move around. Eyes... nose... hm, or maybe they are cyborg organisms.
Hm... or maybe just completely robotic, having already killing off their "creator race". haha... now THAT would scare the heck out of me.