Since the patch, the cvars rawMouseAccelerationEnable, rawMouseRate, and rawMouseResolution seem to have been removed. The cvar rawMouseEnable appears to still be working, but it has no effect on acceleration of the mouse cursor.
There appears to be a new cvar added with the patch, “mouseAccel”. Unfortunately, this cvar returns nil. It appears to be completely non-functional. This leaves us with no way (as far as I can tell) to actually turn mouse acceleration for the cursor itself off. I am not experiencing any acceleration using mouselook, which is odd. It looks like something specific to the cursor itself is causing this issue.