From the release:
"We wanted to share a quick update on the status of the Crackdown demo, recently scheduled to appear over Xbox Live Marketplace on Thursday, January 18th. The demo is going through the final steps of the certification process, pushing the scheduled release by several days, though it is still on-track to appear before the end of January."
The release goes on to state that the co-operative play will not feature the "robust, jump-in-anytime and play cooperative mode" that the retail version will have. Nor will it support join-in-progress gameplay.
Other tidbits include:
-Players will be able to fully explore one of the four major gang-held territories available in the final game.
-Agent leveling is enhanced in the demo to provide a better understanding of the advanced abilities of these physically augmented peacekeepers.
Crackdown (with that coveted Halo 2 beta) will hit retailer stores on February 20th and be rated 'M for Mature'.