Looks a lot like a cross between an alien invasion game and SauerBraten (Quake style fps: http://sauerbraten.org/ )
http://www.forgeplanet.net/
[video=youtube;YxBSYit49c8]http://www.youtube.com/watch?v=YxBSYit49c8[/video]
http://www.forgeplanet.net/