If WW numbers are close or a draw, The American numbers could give the 360 the world wide win before the end of the year if the ratio from this year and last year holds true. I would suggest its better for the 360 this year than last year in Americas so its definately a possibility.
VGChartz Hardware data for the period 03rd Nov 2007 to 05th Jan 2008:
Console PS3 X360
America 1,380,959 2,221,898
Tease.







