It fluctuates a bit, but usually around 35 to 45% of all sales for the year happen between the end of October and the end of December. To wit, last year's percentages were 34.94% of Wii sales, 42.38% of PS3 sales, and 38.09% of 360 sales in the weeks between the weeks ending 9 Nov and 28 Dec; if it were possible to get a breakdown from 31 Oct to 31 Dec, it'd be even closer to 35% to 45%.
That said, with estimated data inputted for the rest of the weeks of October, the spreadsheet gives me these projections:
Wii: 9,417,830 to 14,074,812
PS3: 4,677,739 to 6,985,509
360: 3,490,690 to 5,281,391
They'll probably turn out to be not too terribly accurate, because 2008 has done its damnedest to not to be anything like 2007, but we'll see.
Sky Render - Sanity is for the weak.
