Matt, I'm still having issues with the corruption in the bottom right-hand corner. The problems in the video have disappeared. Also seen another person in the official GTA thread with the same issue.
Does disabling AA (normal and reflective) solve the issue?
MSAA appears to be the culprit. Disabled all AA and it disappeared. Enabled FXAA and reflection AA and it stayed away. Enabled MSAA and it came back.
Superpatsy, could you just confirm to me please if you were running DirectX 11 when the corruption occured? Thank you.