From AMD marketing:
"AMD FidelityFX Super Resolution 2.0 technology is a temporal upscaling solution with incredible image quality that is the result of many years of research into upscaling technologies. It has been built by AMD from the ground up to deliver similar or better than native image quality and help boost framerates in supported games."
"FSR 2.0 temporal upscaling uses frame color, depth, and motion vectors in the rendering pipeline and leverages information from past frames to create very high-quality upscaled output and it also includes optimized high-quality anti-aliasing. Spatial upscaling solutions like FSR 1.0 use data from the current frame to create the upscaled output and rely on the separate anti-aliasing incorporated into a game’s rendering pipeline. Because of these differences, FidelityFX Super Resolution 2.0 delivers significantly higher image quality than FSR 1.0 at all quality mode presets and screen resolutions."
Video explaining it:
The short of it?
It boosts performance, while giveing pretty much near equal image quality.
Zoomed in on screengrabs: (left most = native 4k, then FSR 1.0, and lastly FSR 2)
(left most Native 4k, then FSR 1.0, and lastly FSR2.0)
PCgameshardware.de has a tool for compairsion if you want to see for yourself: