One of the modes will be called Anarchy and it's basically a survival mode where you and three friends face off against increasingly difficult waves of enemies. You also have to kill the enemies in specific ways in order to generate skill points, which is one of Bulletstorm's main features. The other mode that was revealed is Echo which is actually played as a single player mode but does contain multiplayer leaderboard support. In this mode you play any of the game's levels and try to get the biggest skill score possible and compare your results with your buddies on the leaderboards. Bulletstorm is still due for release on February 22.
Gallery: Bulletstorm Screenshots