On my system, (fairly high end), I also can not get past the load screen to login. I hear the sounds change as I press the space bar but no video intro changes. This is also happening with SC so I doubt it is an issue with the latest MWO patch.
Tried rolling back but I have a feeling windows is now trashed as that failed to solve the problem. Next step is to try a Win10 install on my gaming machine which I was hoping to avoid for at least a little while.
Win7(64bit), R9 290 video card
Update :-
removed the Crimson driver, rebooted, used AMD clean uninstall utility, rebooted, installed 14.12 drivers - pre windows 10, rebooted. ran MWO repair utility.
Star Citizen now works, but MWO still stuck at the first loading screen after you press "play".
Update - Fixed

Used windows restore to go back before I downloaded the Crimson drivers !! Yeah

Still on drivers that are a year old, but that's better than no MWO !!!
Edited by Markoxford, 04 December 2015 - 06:26 AM.