Why set the chart to 156 weeks when 110 will do?
http://vgchartz.com/hwlaunch.php?cons1=Wii®1=All&cons2=PS3®2=All&cons3=X360®3=All&weeks=110
It's easier to see divergences, especially the tiny divergences between the PS3 and the 360, when you're looking at a tighter chart.
And, as you can see, we're just about to get into Microsoft and Sony's terrible part of the year: January through September.