"Nintendo 3DS broke Enterbrain's monthly sales record in December. According to Sankei News, the system sold 1,492,931 units over the month. This is the highest single month sales total since Enterbrain started tracking sales in 1997."
That number is even more impressive when you compare it to the Vita which launched in the same month. The 3DS sold over 1 million more systems than the Vita even though this was Vita's launch and the 3DS had already been on shelves for almost a year in Japan. The price cut to go along with the amazing games for the holiday have proved to be a killer combination not only for the 3DS in Japan, but also in the United States.