Sales of Nintendos nostalgic NES Classic Edition were up 14 percent compared to November, its debut month that saw it move 196,000 consoles. Meanwhile, Pokémon helped the aging 3DS portable grow its sales by 2 percent from December 2015.
Source: http://m.neogaf.com/showthread.php?t=1335944
That should be approximately 223,440 units for December in the US for the biggest part of the retail season, a 14 percent increase from November.
Update!
USA: 420,000
Japan: 567,000
Total: 987,000*
*Missing RotW sales.
http://www.neogaf.com/forum/showpost.php?p=227706900&postcount=727
Famicom Mini Classics still outsold US region NES Mini Classics.