I remember when everyone thought it was crazy 2-3 months ago, but now, the PS4 has without a doubt reached +11M only with Destiny, and the big games and christmas are coming.
Now, i say we could even expect 17M.
Predictions for end of 2014 HW sales:
PS4: 17m XB1: 10m WiiU: 10m Vita: 10m