The Official Battlefield Blog announced recently that there will be a Bad Company 2 demo to be released prior to the game’s release date. Announced along with this was changes made to the game’s multiplayer since the PS3 closed BETA as well as a confirmed BETA for PC players.
Although an official date was not given for the demo, you can probably expect it to be released around mid to late February. EA would want to make sure you got enough time with the demo before the game’s release. More details will be posted on the site as they arrive.