I can see PS4 hitting $199 during BF. Whether or not PS will drop the PS4 and/or Pro $50 later in the holiday season to absolutely crush any chance of an XB1 revival with XB1X is really hard to say.
If they price cut this holiday, then next years sales should be slightly less than this year. If they hold the current pricing for the rest of this year, and hit $199 and $299/$349 next year, you will probably see 20M+, 2018 sales.
PS1 - ! - We must build a console that can alert our enemies.
PS2 - @- We must build a console that offers online living room gaming.
PS3 - #- We must build a console that’s powerful, social, costs and does everything.
PS4 - $- We must build a console that’s affordable, charges for services, and pumps out exclusives.
PRO -%-We must build a console that's VR ready, checkerboard upscales, and sells but a fraction of the money printer.
PS5 - ^ -We must build a console that’s a generational cross product, with RT lighting, and price hiking.
PRO -&- We must build a console that Super Res upscales and continues the cost increases.
