Just reporting something odd here:
The most recent NVIDIA drivers (GTX900 series drivers at least) seem to screw with the game's scaling. Rolling back to the second most recent driver was the only thing I could do.
I'm not sure whether this is caused by NVIDIA or the new MWO build but nonetheless, had this problem.
Basically, when selecting my native resolution of 1080p, the game would either run in 720p fullscreen, or in a small window center of the screen. When fullscreened, the mouse would only move within a box in the middle of the screen, rendering anything outside this invisible box inaccessible.
On Windows 8.1**
Edited by xeromynd, 19 August 2015 - 06:37 AM.