The amount airshipped for the holidays is impossible to know. But the effect of lower the supply that normally would come by boat is also hard to know. If massive amounts were airlifted, there could come a time in late Jan/Feb where no or very little shipments (via boat) are arriving.
I thought that the rain checks were only for Game Stop. If so, only Game Stop will show more outages than the rest, with most that it receives should be going to those that bought rain checks. Which appear to be already being redeemed.
But in a few weeks, should show where this year's bottom is for Wii, PS3 and X360. A month from Xmas last year showed where all three machines were to average out until the fall selling season started up for the big games coming out in time for the holidays.