Here are the release notes of this initial patch:
And here's a list of key issues the developers are working on right now:Fixed a crash that was happening for some users when exiting the game Fixed a bug which disabled rain effects and ambient occlusion. We are actively looking into fixing other bugs to improve this further Corrected an issue that was causing Steam to re-download the game when verifying the integrity of the game cache through the Steam client Fixed a bug that caused the game to crash when turning off Motion Blur in BmSystemSettings.ini. A future patch will enable this in the graphics settings menu
Robert Cram took a look at the post-patch PC version and compared it with footage from the console version of Arkham Knight:Support for frame rates above 30FPS in the graphics settings menu Fix for low resolution texture bug Improve overall performance and framerate hitches Add more options to the graphics settings menu Improvements to hard drive streaming and hitches Address full screen rendering bug on gaming laptops Improvements to system memory and VRAM usage NVIDIA SLI bug fixes Enabling AMD Crossfire NVIDIA and AMD updated drivers
And here's the same comparison with the pre-patch PC version:
Source: DSO Gaming