Did the scarce Wii benefit console competitors?

December numbers would seem to suggest the scarcity of the Wii may have benefited the other consoles.

"While the Xbox 360 and the Wii sold roughly the same amount of units in December, in terms of growth, the Wii was the clear loser. Nintendo’s red-hot game system saw a 38 percent increase from November to December, versus 64 percent for the Xbox 360 and 71 percent for the PlayStation 3."