Let's see a possible scenario...
XB1 this November: 900,000 ( i personally predict 1.02m )
Wii U this november: 400,000 ( i personally predict 325k)
Now, last year, Wii U got a 140% boost November to December, ( 242,000 -----> 580,000 ), and XB1 only 5% boost ( 1,230,000 -------> 1,290,000 ).
IF we will see those sales in November, and we will see the same boost of last year, then the December result will become:
Wii U: 400,000 + 140% = 960,000
XB1: 900,000 + 5% = 945,000
Ok, not gonna happen, but lmao if will.