Considering the source, I'm loathe to take this as gospel, so consider that yourself when looking at this news, but it looks like the Wii U might have outsold Microsoft's new-gen machine in the week leading up to Christmas, though not by much.
The figures on this come from VGchartz (via Forbes), which doesn't have the cleanest of histories when it comes to sales numbers, but if true, it's certainly exciting for Nintendo.
According to the stats, Nintendo's Wii U sold over 319,000 units in the week leading up to Christmas, whilst Microsoft's Xbox One only managed 307,000. It does need to be considered that the Xbox One hasn't launched in Japan yet, where over a third of the Wii U's sales came from, but considering less than a thousand Xbox 360s were bought by the Japanese in the same period, it would be surprising if there was a mass of Xbox One sales even when the console lands sometime later this year.
Sony will be giving itself a pat on the back though if all these numbers are true, as not only did its PS4 outsell both Microsoft's and Nintendo's home consoles (with more than 650,000 units sold) but so did its ageing PS3, with more than 400,000 sales.
However, king of the hill was the 3DS, pushing over a million of itself into the hands of eager gamers everywhere. It's worth noting too, that the 3DS had a very slow start when it came to sales, but has now become a very dominant contender. Perhaps the Wii U is heading for something similar now it seems to be picking up steam?