[kupoartist]

Source: www.beyondunreal.com
"Unreal II: The Awakening" for Xbox will include a robust multiplayer component both on- and off-line. Two players will be able to join forces in splitscreen co-op mode to battle through the epic single player campaign as a team of mercenaries. Online play will be supported through Xbox Live! and will feature an all new class-based, team-oriented multiplayer mode.

Details about the XBox version of Unreal 2 are pretty scarce, but I think this suggests that the Christmas released version of the PC game will have some kind of system link functionality? It'd be nice enough to have another co-op game i suppose. (and you mentioned U:C anyway, so this is the next best thing)

And speaking as a fan of the Unreal Series... perhaps the XBox version will right the wrongs of Unreal 2. Releasing a PC game with no multiplayer is just suicidal. Hopefully the multiplayer will make the game seem longer. It seemed very, very short when I played it this Spring.