With typical spartan terseness, Major Nelson has dropped news of the latest demo available on Marketplace:

Xbox Live members can now download a demo of 'FCIP' from the Xbox Live Marketplace. This content is not available in Asia.

That mysterious 'FCIP' stands for Far Cry Instincts Predator, which is at least one Crytek game that the 360 appears not to be too powerful to handle. Florian Eckhardt

Far Cry Instincts Predator [Major Nelson]