It seems that japan is getting Vanquish during october,or to be more precise,october 21.October is also the month of the international release.
http://www.siliconera.com/2010/07/07/japan-gets-vanquish-on-october-21/
http://www.siliconera.com/2010/07/07/japan-gets-vanquish-on-october-21/