Upgraded from 6.1.9 to 6.2.2 yesterday without issues.
All the info gathered by the mods and included in the 2nd post of the 6.2 release thread was invaluable.
http://lime-technology.com/forum/index.php?topic=51874.msg497876#msg497876
Parity sync was finished this morning and I have two valid parity drives.
The only thing left on my to do list is to pull the cord for the UPS out of the wall and verify I get a clean shutdown of unRAID and my VM's.
BTW, I had to go to 6.2.1 first as 6.2.2 didn't show as an update until 6.2.1 was installed.
Once 6.2.1 was up and running, 6.2.2 showed as an available update.
Not sure if that is by design or not so I thought I would throw that out there.
Anyways, I'm really happy with how the upgrade process went.
Very good work guys!