I've run into an issue with 10.8 where X will go berserk (100% CPU, impossible to kill) when the screens go into DPMS off state. Screens won't turn back on. SSH'ing in shows X at 100% CPU, doesn't respond to kill (even kill -9) commands, reboot the only option. Ubuntu 10.04, Compiz, HD5770.
No announcement yet.
Catalyst 10.8 released...