I think:
-Both the PS4 and Xbox One will both be around 3 - 5 Million by January 1st (Depends how much each company ships)
-Both PS4 and Xbox One will hit 10 million by the end of June 2014
-PS4 will near 20 million by the end of next year
-Xbox One will be at around 17 Million by the end of next year
-Wii U sales will be at around 12 million by the end of next year
What do you think?