Diogo on 02 October 2018
I would go with 2021, Sony is enjoying a lot of success, they will surely want to extend PS4 sales for as long as they can. However, I would not be surprised if it ends up being 2020. It will be interesting to see how Microsoft will attack the next generation (they've alread begun with the aquisition of those development studios), Microsoft's next machine may indeed determine PS5 release date.
