Ah, I didn't think there was so many joke posts when I looked at this thread ;D
Well:
I also think that it should be about 6M as of today (nov 19).
Prediction: End of 2015 Hardware sales (as of January 20, 2015)
Wii U: 12.1M | XBO: 19.8M | PS4: 36.0M | 3DS: 58.5M | PSV: 11.7M