Update Your OS X Mountain Lion App to 10.8.3

[MichaelBhea]

Article: Update Your OS X Mountain Lion App to 10.8.3

Same thing here, screen just locks up, mouse keeps moving. Been running in -x mode for the last week - update sucks.

Seems you may be a victim of the "Fermi Freeze"... do you happen to have a GTX 560 Ti or GTX 460 v2 graphics card? those two seem to be the worst culprits so far.

best bet for these cards so far is to remain at 10.8.2 and HOPE that 10.8.4 will fix this...