Mac users don't all have the same experiences, I've been able to use Firmware Update method since
it became available for my camera (A720IS), it was not a drama to load to SD card (although 4GB not 8GB).
I used the Mac Applescript to prepare the card, with a couple of variances, without need to do any
Terminal procedure at all.
Even though I do use AppleOff (an application) to clean removable storage media of .DS Store and .Trashes files,
those do not stop manual or auto start.