Thanks to everyone for all the numbers they offered.
Both PS4 and One did pretty well this December, PS4 with a huge increase YOY. Weekly averge is lower than November, and numbers overall didn't change that much from November to December, but it's better than last year IIRC, so some progress after all. Interested to see what's going to happen next year, when the MSRP for both should be 299.99, thus Holiday deals will bring a lower price: that price + huge games in November brought sales on fire, especially compared to so many anemic months earlier in the year. Didn't expect the gap between the two to be this small for December, surprised.
Wii U is about its zone, more or less, despite the bad Holiday lineup, in terms of relevant releases. Bad, but steady after all. 3DS is down a bit less than what I thought. These Holiday numbers are Nintendo's fault, alongside the platform aging: no big deals at all (unlike the Splatoon/Smash bundle for Wii U), no huge releases for Holidays. Nintendo consoles continue to see a more traditional November-to-December uptick anyway, whatever the sales are / the deals in place are, though.
This doesn't mean Nintendo really didn't sell that much software this year, even if in a bad year by their standards. More on this later, except for...
...well, Xenoblade X. 200k+ (without digital) might not be an incredible first month, but it's, indeed, a quite good debut for a JRPG on a Nintendo home console without a mainstream advertising (it was promoted, and it had TV ads, but it surely wasn't promoted as much as major AAA/AAAA releases at all). Heck, it's actually a good debut for a JRPG in general that's not part of the big series.
This actually makes me wonder (and I hope whoever can helps here): we have a JRPG not from big series (FF, Pokemon, Mario, etc.etc. ) selling more than 200k at retail on a Nintendo home console in the first month. When was the last time this happened? I can't remember, honestly.