From Rock, Paper, Shotgun:
Jim:: Yes, it’s very much in that school of Oh-This-Is-Aliens-From-A-Top-Down-Perspective
John:: But unlike Shadowgrounds and others, this is four-player co-op. And without four, it’s not really worth trying.
Jim:: And, sadly for Team 17, it makes Alien Breed Evolution look a bit stiff and uninspired. Which is a shame, because that’s a fairly entertaining game.
John:: Yes. Valve making a free game in your genre must be a bit like entering a county fair chilli cooking contest, and finding out Anthony Bourdain is participating.
Jim:: Yes. However, in conclusion, we can only take this game as evidence of showing off.
John:: Absolutely.
Jim:: Valve are no longer a game development company, but a showing off company.
John:: “We thought we’d make the best example of this genre in our spare time.”

Here.