That's incredibly pessimistic 

I'm all for PS4 reaching high numbers, but it won't reach 18 million units sold by the end of the year. Maybe 14-15 million, and that's being generous. Still, it will have a comfortable lead over the other two.

18M is the minimum.

20,000,000 is my bet.

Definitely a possibility wih heavy hitters such as AC Unity Far Cry 4 and Dragon Age.

Well all the 3rd parties give a bigger boost to PS4 even when it is advertised on Xbone. Despite that Sony is keeping their foot on the third party peddle this holiday with FC4 and GTA5 bundles and most likely ads. Destiny is still selling which is heavily favored on PS4. They have LBP3 which is a huge family title and promotes co-op. They need a bundle with 2 controllers and LBP3 for $450 called the family pack and they'll be golden this holiday with some good ads. I'm thinking they'll make it.

If it gets to 18 million before the end of the year that would be a fantastic achievement. Personally I think its a touch unrealistic. I think your looking at something between 15-16 million myself. Thats still 3-4 million in what, 9 weeks?

Absolutely. It should already be at 13 million+ by the end of 2013, doing 5 million in Nov + Dec. is completely possible if stock allows (this is the big one here, I think stock is going to be a big issue).

The PS4 will have a 10 million unit lead over the X1 by the end of 2014, 22 million+ by the end of 2015.

How can anybody believe that the PS4 is only going to sell 15 million by years end? How is such a low estimate feasible in any way? Even with supply problems 18 million should be easy.

Ask again after November

18.7m. Heard it here first