Just a few hours ago, Eidos released the PC demo for Conflict: Denied Ops. However, a scan from the Dutch gaming magazine Power Unlimited confirms that there is an Xbox 360 demo incoming as well. The ad in the magazine says the demo is already available on Marketplace, but as you might know this is not the case yet.
The demo is expected to launch in the next few days on Xbox Live Marketplace. Any details on a Playstation 3 demo are yet to be revealed.