My friend just got a 360, with the intention of the two of us playing multiplayer and co-op campaing mode. I guess he amazed a clerk at gamestop when he brought back Armored Core 4, but its multiplayer set up bit, so he did not keep it.

Finished HALO with him just last night,

Also have and intend to play

Crimson Skies
Counter-Strike
Halo 2
Halo 3
Army of 2
Gears of War
Ghost Recon: Advanced Warfighter.

We are looking for other games that have a good Multiplayer Set-up, and taking advantage of games that allow cross-over to x-box. If it has X-box live, we want to BOTH be able to play,