Anything prior to the 400 series is not supported in this release (mentioned last time).
HD still does not support 144 Hz, sadly.
Improved performance for Dying Light, which is pretty important to me. A hand full of other SLI profiles added.
The screen flicker in Company of Heroes on SLI systems is still not fixed.
Using the Negative LOD Clamp setting on 400 and above video cards does nothing.
The rotate display function (portrait mode) has changed to match the Microsoft Display panel. Mine adjusted automatically, so probably not an issue.
There are many other changes I didn't mention here.