I have worked with personal computers since the days of DOS. I’ve loaded and upgraded every incarnation of the Windows OS, worked with a number of Mac OS versions and have been tinkering with GNU/Linux for about half that time. That said, I have NEVER seen an upgrade of an OS as smooth as my recent upgrade from Ubuntu Linux 7.4 (Fiesty Fawn) to 7.10 (Gutsy Gibbon). The steps are detailed on the Ubuntu site. And, they are just as easy as shown.
In my case, I was plugging away at my tasks utilizing the multiple desktop feature of Ubuntu which allows you to place different applications on different virtual desktops and switch between them. My update manager popped up with the message that new updates were available. I saw this notice:
I clicked on the Upgrade button and continued working on the various applications I had opened. A few times I had to approve some action, but everything downloaded in the background as I worked away. After some time (I really don’t know since I wasn’t keeping track of time) I was notified that updates were complete and after a reboot I was there. I have never seen an easier upgrade. Kudos to the the Ubuntu community.