Here is a NSMB (DS) comparison to GT4
Japan: http://vgchartz.com/swlaunch.php?reg1=Japan&game1=New+Super+Mario+Bros+-+DS®2=Japan&game2=Gran+Turismo+4+-+PS2®3=All&game3=&weeks=26
(NSMB wins easily)
Americas: http://vgchartz.com/swlaunch.php?reg1=America&game1=New+Super+Mario+Bros+-+DS®2=America&game2=Gran+Turismo+4+-+PS2®3=All&game3=&weeks=26
(GT4 wins just... but bare in mind PS2 was incredibly popular back then, wheras DS in America was a slow starter)
Others: http://vgchartz.com/swlaunch.php?reg1=Others&game1=New+Super+Mario+Bros+-+DS®2=Others&game2=Gran+Turismo+4+-+PS2®3=All&game3=&weeks=26
(GT4 wins easily.. but again NSMB launched before DS was up to speed in Others)
Overall: http://vgchartz.com/swlaunch.php?reg1=All&game1=New+Super+Mario+Bros+-+DS®2=All&game2=Gran+Turismo+4+-+PS2®3=All&game3=&weeks=26
NSMB wins, but mainly because GT5 had a more staggered launch.
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So I would say first 26 weeks will probably be about this:
Japan:
NSMBW - 1.5 million
GT5 - 800k
America:
NSMBW - 3 million
GT5 - 1 million
Others:
NSMBW - 2.25 million
GT5 - 2.75 million
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So GT5 will reign in Others (though I expect NSMB might catch it eventually) but in America and Japan NSMB should easily triumph.








