I have a three month old 13" MBA and it freezes indiscriminately. I can't move the mouse and the keyboard does not respond. The only option is to power down the laptop. I have found it always freezes in the midst of repairing permissions. Always. I booted to the recovery mode and the repairing of permissions did not freeze then. The laptop has Mountain Lion 10.8.2 and other updates. Any suggestions to resolve these issues are appreciated. Thanks for looking.