As far as I know, HDR on PS4 will arrive in January.
At this point the only things CDPR needs to address are:
1) Performance mode for PS4 Pro
2) HDR for PC version of the game
I would love to get especially the performance mode. My PC isn’t very powerful for now, and I wish to play the game in that mode. Given that PS4 Pro’s CPU is slightly less powerful than Xbox One X’s(same Jaguar CPU architecture basically, just a bit downclocked on Pro in comparison with X), I think it is possible to pull it out on a Pro, with any nececcary graphical sacrifices-I’m more than willing to go for them if needed to, I personally don’t mind. Perhaps it would be better to not to have any sort of 4K in that mode, but again, 1080p-720p dynamic resolution scaling.
For PC users though, I think it would be very good to implement HDR. They have got every possible graphical setting to be tweaked in the game, and the only thing missing in that regard is HDR support. I mean, don’t you, CDPR, would like to see for yourselves how the game would look like on Ultra settings, with HDR enabled?…indeed, it would be fascinating to see to say the least.