Heres the article:
http://www.joystiq.com/2007/11/09/xbox-360-outsells-ps3-in-japan/
Apparently Ace Combat 6 pushed the hardware units for xbox 360 by close to 500%, even more then Halo 3 did, and it even ranked second behind SMG.
While they say Xbox360 only sold 200 units more then PS3, this is pretty ridiculous, and i think most people might say totally unexpected.