Serenity Painted Death said:GC is at ~4 million.
Xbox at ~450K
PS2 at ~23 million
Japan / Asia
PS2 - 22.83 million
Xbox - 2 million
GameCube - 3.98 million
Xbox 360 - 0.1 million
Game Boy Advance - 16.47 million
PSP - 4.2 million
Nintendo DS - 5.7 million
http://forum.pcvsconsole.com/viewthread.php?tid=8498&page=2
Regardless I agree it is improbable for 360 to hit 6million in Japan, but stranger things have happened.
The big thing MS needs to do in Japan is make j-devs realize they can still make money with their software on sales outside of Japan. They seem to be on the right path in this regard. Hopefully as this software library builds it will become a much more viable option in Japan ...eventually.