I had originally planned to wait some weeks to upgrade, to permit the new version to be seasoned. But Tuesday, I found myself with extra time, and decided to upgrade.
I launched FedUp using the command line (I hope one day FedUp will have a GUI, but the command line is easy). It began seamlessly downloading the packages. Then it had me reboot.
When I rebooted, the little Fedora insignia began flashing as the install took place, just like when I upgraded from F18 to F19. This time, though, the upgrade seemed to complete itself in record time. Unfortunately, though, the system merely logged me back into F19.
I went to the Fedora IRC to ask about the issue, and got one bit of slightly helpful advice and mostly not much advice at all. I tried to update a bit and try again, but ultimately, gave up the effort.
This morning, a weblog post over on Fedora Planet advises that FedUp .7 has an upgrade to .8 that will be required to do the upgrade. Ideally, of course, they would have upgraded FedUp before they released F20. But it's no big deal.
Fedora has a reputation for being so cutting edge that its package stability can be imperfect, but this is only the second minor glitch I have encountered with Fedora since January (the first was when an upgrade temporarily impaired Virtual Box, after which a later upgrade fixed it). I'll try again later, and expect it will work fine.
The lesson I took is my usual lesson--don't upgrade an operating system on the first day of the upgrade release, a corollary of the rule that says don't buy a car in its first year model.