I just finished the upgrade of my servers from Ubuntu 8.04 to 8.10 (yes, I prefer numbers instead of Hardy, Gutsy, ... it's so difficult to remember their year/month release date).

This was the first time I completed the entire upgrade remotely, through an SSH connection; no CD or DVD, just an internet connection.

It was about a 600Mb download, completed in less than 4 hours, followed by a reboot.
The server restarted successfully and, voilà, the new Ubuntu 8.10 is ready to go!
The greatest thing of all was that all the services of the machine were available, up and running during the upgrade... excluding the reboot time.

Just to be clear, it was not a mission-critical machine; anyway a fault during the upgrade required me to move physically to the remote location.

I still wonder what command should I run to upgrade my XP clients to Vista... :)