My only gripes are that it sounds like you are shooting toy guns for most of the gun sounds, and the people (aliens) sound like you are hitting a bag full of jelly...squishing every time they get hit. Also, I hope the music is a lot better when the game comes out... it was the same song the whole time. The guy who's speaking to you over the radar sounds a bit cheesy....
Besides that, this game looks pretty cool. I hope the overall atmsophere and story play over well.