It should be? What gives you reason to think it isn't possible?

Just asking since I've only been using Ubuntu for a few weeks.

I don't think he means "technically" possible. I think he just mean "How can I?".

Should be possible via update-manager soon enough. Even major upgrades (6.04 -> 7.04 etc) have been possible for a year or two at least.

Minor niggle: it was 6.06; they delayed that release by two months in preparation for their very first LTS release.

And another one: you can upgrade 6.06 (a Long Term Support release) directly to 8.04 (the next Long Term Support release), but to get to 7.04 you had to do incremental upgrades to every intermediate release (6.06 -> 6.10 -> 7.04).

Yeah, of course.

    sudo apt-get update
    sudo apt-get dist-upgrade

That's an unsupported upgrade method. Please issue "update-manager -d" in a desktop install, or "do-release-upgrade -d" on a server or other command line environment.

And before people complain about the command line, this is possible in the GUI as well.

System - Administration - Update Manager

Click "Settings"

Under "Updates" select "Show new distribution releases: Normal releases"

By default if you are running an LTS release, Update Manager assumes you want to update only to the next LTS release. This setting will cause it to prompt you to update to the next non-LTS release and each other from then on.

I guess this is a tiny point, but is there really no supported way to update from the command line?

or "do-release-upgrade -d" on a server or other command line environment. (emphasis mine)

Wow, I'm a genius today. Thanks, though.

"sudo do-release-upgrade" is the supported command-line upgrade method.