Comment 4 for bug 1302270

$ ls -l /dev/dri/
total 0
crw-rw---- 1 root video 226, 0 Apr 3 19:38 card0
crw-rw---- 1 root video 226, 64 Apr 3 19:38 controlD64

This seems to be normal. I also was not in the video group, however if I add myself to the video group, logout and back in, then I don't have the .xsession-errors and I unity7 is responsive again. Not sure what would cause me to have to be in the video group all of a sudden, but it does seem to be a workaround.