I say yes, Why? Most 360 exclusives have split screen with online play.
1. Halo 3/ODST
3.Forza 2/3
4.Gears 1/2
5.L4D/L4D2
Not to mention the multiplatform games such as
1. CoD WaW/MW2
2.RE5
3.Army of two
those are just some of the multiplat split screen games.
Sure 360 devs may not be pushing "100%" out of the console like they do with other consoles but they are focused on making the game fun and get good sales so they can produce a sequel. Games like Left 4 Dead and Halo 3 ODST firefight mode is a big addition for games these days, it seems like almost ALL games come out with a type of mode like that. COOP is the new multiplayer, almost every shooter is gonna include some kind of COOP game mode, even Modern Warfare 2 will be including a COOP mode.
This is why 360 exclusives and MOST multiplatform games sell better on Xbox 360,
Xbox 360 is F_U_N to play!!!
Edit- its like watching a movie, you can watch it by your self or with friends and have a laugh, with friends its more likely to be enjoyable.









