3rd December 2019 is the 25th anniversary of the launch of the first playstation. I thought for sure they would have an event this year revealing the ps5 but they've said PSX isn't happening this year. I guess it could still happen. But if not then we'll get it revealed February to April.
Predictions (Made July 2019)
LTD: PS4 - 130m, Switch - 110m, XBO - 52m 2019 : PS4 - 15m, Switch - 18.8m, XBO - 4.8m 2020: Switch - 22m (Peak Year)