According to this post from Kotaku, it may not be...
http://kotaku.com/5286896/xbox-japan-accidentally-uploaded-final-fantasy-xiii-page
Currently I'm not sure if this game will be out for Asian/Japanese Xbox 360s, considering that the FFXIII trailers and themes on the marketplace are only available for US accounts. It would be a real shame if it were only out in the USA; there's a lot of JRPG fans in Asia, and of course in Japan....that said, the 'accidental' posting of that page gives some hope for Final Fantasy fans who prefer the Xbox platform.
http://kotaku.com/5286896/xbox-japan-accidentally-uploaded-final-fantasy-xiii-page
Currently I'm not sure if this game will be out for Asian/Japanese Xbox 360s, considering that the FFXIII trailers and themes on the marketplace are only available for US accounts. It would be a real shame if it were only out in the USA; there's a lot of JRPG fans in Asia, and of course in Japan....that said, the 'accidental' posting of that page gives some hope for Final Fantasy fans who prefer the Xbox platform.