Following yesterday's announcement by Microsoft that they sold three million Xbox One units, Sony Computer Entertainment revealed that a whopping 4.2 Million Playstation 4 units were sold as of December the 28th.
By the first week of December the Playstation 4 had already sold roughly 2.1 Million units, and the numbers kept steadily rising up till today. The Xbox One on the other hand started off strong, but sales have been rapidly decreasing since mid December.