Well first time Mac use since March. Was all excited that I get to do a 10.5.x upgrade. I just went via SU. It downloaded, rebooted once and installed perfectly and quickly. All came back up and all is sweet. Literally 1 minute after the Mini finished updating, BOOM! - power outage!!!! Neighbours, the whole street black .... Very lucky the update finished JUST before the outage I remember reading that you are not supposed to turn the thing off when it's updating (which makes sense).