Argh! I spent about 5 hours yesterday troubleshooting a failed Ubuntu Jaunty -> Karmic (9.04->9.10) upgrade. It worked fine until I rebooted and then failed to boot. Here’s how I fixed it.
It failed to boot, saying this:
One or more mounts listed in /etc/fstab cannot yet be mounted
/ : waiting for /dev/xvda1
/tmp : waiting for (null)
/swap : waiting for /dev/xvda9
I tried a lot of stuff and finally solved it. My solution is on the Ubuntu Forum, here: One or more of the mounts listed in /etc/fstab/ cannot yet be mounted (Karmic).