Looking at the pic of the 3 guys, since I'd never watched the trailer, it definitely suggests 3 player co-op. Co-op and multiplayer gaming does seem to be the strength of the 360, since it is so easy to organize and manage drop in/out games with your friends. You have the tools to communicate, invite and join very easily. Could there be cross-platform play with the PC? Maybe, but I doubt it. It wouldn't be a huge stretch if it ended up being available on games for windows live. Maybe there are some new Live features coming in a fall update or at some point that this game will leverage.