Maybe we need another poll.
How sure are you that your backups work?
I have upgraded all of my PCs from Ubuntu11.04 to 11.10.
2 netbooks, 3 desktops, 1 laptop.
All upgrades in place, and no problems.
I always leave my Mythbuntu box until last. Lulled into a false sense of security, I didn't do a full backup, all the data is on a separate drive, so I just manually backed up my Zoneminder and MythTV databases, and /etc.
Disaster! after the update, X wouldn't start, in fact I was lucky if I got a command line after a reboot.
Some sort of driver issue, but after messing with xorg.conf, I still had no x screen, and even the CLI wasn't a given.
So I thought "about time for a refresh anyway" this PC has been upgraded every 6 months or so since Mythbuntu first went on it, 8.10 or 9.04.
restored zoneminder database backup.
tried to restore MythTV database "unknown object in backup file"
It was around then that I found that all of the recent automated backups were 0 bytes in size.
After some frantic Googling, found that this error can be caused by the restore routine barfing over a large (40M+) file.
split 57M backup into 2 files, restored each- breathe sigh of relief.
The sig between the asterisks is so cool that only REALLY COOL people can even see it!