That is to be the best selling home console every week for a full year. Wii almost made it in 2008, but it got pipped by PS3 on 14 June 2008.
So far PS4 is unbeaten in global (as in world wide) weekly sales.
As you can see Xb one got close twice, and Wii U got close-ish once.
Possible weeks where Xb one can be the highest selling: China launch week, Halo MCC (11 November), Black Friday (28 Nov?).
Possible weeks Wii U could sell more than PS4: Smash week (date?).
There seems to be some disagreement over whether China launch was 100K sold or 100K shipped, but if it's 100K sold then it's very possible Xb one wins that week, just depend how much of a pre-holiday season lift PS4 maintains with Destiny and Fifa legs. I expect Fifa week PS4 sales to be substantially higher than Xb one, despite the exclusive Fifa deal with Xbox because continental Europe will still go for PS4 in far greater numbers. But whether that means the 2nd week drop for PS4 will be small enough to keep the gap large enough for China not to make up the difference it the big question. I don' think Halo MCc is a big enough global draw to make much difference. It will give Xb one the top sales for the week in USA and UK, but that's all and not by a big enough margin.
By the time Smash comes out the Holiday season sales will be in full swing. It will sure give Wii U a big lift, but Wii U is so far below PS4 I'm not sure it can make up the difference without a price cut at the same time.
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