Aliens vs. Predator is a Capom-published action game that features both aliens and predators, but I'll bet you'd already guessed that. It's for the 360, the PlayStation 3, and the PC. In it, you'll be able to play as an Alien, a Predator, or a Colonial Marine -- that's what I call variety!
I'm sure you'll want to see the trailer. It is embedded below.