Patch 1.1 just came out and apparently some other game breaking bugs had to be fixed with 1.1.2 patch that just dropped a few hours ago.
Here is a picture showing performance for me (1440p, everything max settings, motion blur off and TAA enabled with 100% scaling):
I'm running with TAA enabled, 100% upscale and while it helps get rid of the chain link fence looking jaggies way off in the distance for me, it causes ghosting and blurring at times with vegetation when you're up close and personal with it. I also see the ghosting when swapping weapons or holstering them:
A couple of the cutscenes where you are supposed to be seeing something on monitor screens in the game, they are just white - there are no images. This happens in two different locations. You can hear the audio and read the subtitles, but no images appear on the screens you are looking at:
Here are a couple of bugs I have come across since the latest patches:
Two NPCs standing in the same spot (or maybe it's a mutant of the Zone!) - also it shows the performance I have while playing.
Here is a spot I found where you fall through the ground. It could just be my personal game, but any saves I have before I encounter this place always allows me to drop through the ground. It happens outside a building in Pripyat. First picture is a look at the building close to the Ferris Wheel, second picture shows the location where you drop through the ground.
I can't say for sure, but there doesn't feel like any kind of improvement in performance for the game from before patch 1.1 and after.
What I can say for sure is that there is almost zero NPCs spawning behind me and kicking my ass after patch 1.1. Also, you get a lot more mutants and NPCs traveling - you will encounter more than you used to.