The only reason why the PS3 is tracking 360's sales is Japan.
If you compare PS3 vs 360 sales in Western markets, the story is different:
http://vgchartz.com/hwcomps.php?cons1=Wii®1=America&cons2=PS3®2=America&cons3=X360®3=America&align=1
http://vgchartz.com/hwcomps.php?cons1=Wii®1=Total+Other&cons2=PS3®2=Total+Other&cons3=X360®3=Total+Other&align=1
It's near the 360 in Europe (but lower), and not anywhere near where the 360 was in America.
My Mario Kart Wii friend code: 2707-1866-0957