My argument wasn't that the 360 wasn't dominating in other regions. My argument was that the type of game that SE makes usually doesn't sell well on the 360, due to the type of gamer that buys a 360, in and out of Japan (points at Blue Dragon). Therefore, multiplat ps3/360 wouldn't help very much, because they wouldn't garner that many more sales from a 360 version of a game.
The idea that 360 versions wouldnt get a lot of extra sales on a japanese game because of the audience i think is a flawed statement. Microsoft has been trying to get japanese developers to make for the 360, and they are slowly but surely doing it, like recent announcement of "Infinite Undiscovery" as an exclusive (someone mentioned its on ps3 too, but Square Enix has announced it as an exclusive) for 360, along with a couple of other japanese games coming out for 360. If they start getting this games on the 360 platform, they can very well start to attract audiences that enjoy those games to the 360 (essentially, they hope to brng sony fans, as PS is more known for having an abundence of japanese games.) then, they can achieve the sales they may be looking for, in time that is.
Oh, another thing about Square Enix always being mulitplatform, isnt this true? yes, their games themselves have been Exlusives to one system or other, but havent they always been making other games for other systems? like doesnt GC, DS and GBA have a couple of those small FFs spinoffs on them? And not to mention that Xbox 360 already has a Final Fantasy game on it, Final Fantasy XI, was one of the first games to come out on the system, if im correct.