Part of my reasoning to hold on to that prediction is
http://vgchartz.com/hwcomps.php?cons1=Wii®1=All&cons2=PS3®2=All&cons3=X360®3=All&start=39236&end=39600
notice how Wii's trend, while continuously jumpin up and down, continues to slowly move up during the slowest part of the year. Plus, you add in the continued increase in supply and the massive amounts I think the Wii will outsell the PS360 this holiday...
I'm right. Wii will be greater than 50% by years end.