The Crysis 2 multiplayer closed beta has kicked off and it appears to be exclusive to the Xbox 360 this time around. Invitations were sent out to community members explaining that the beta is "limited to Xbox 360 consoles only this time around."
Invitees will require an Xbox Live Gold Account in order to participate. The invitation doesn't speciy a start or end date for the beta though. You'd probably need to sign up for the beta token to be privy to that information.
The first Crysis set the bar real high for PC games and with Crysis 2, Crytek is looking to do the same with consoles. It'll be the first time a Crysis game appears on the Xbox 360 and PlayStation 3 in addition to the PC. It also supports 3D right out of the box.