With the release of Fedora 13 about a week ago, I decided that my Fedora 11 workstation was getting a little long in the tooth and was due for an upgrade (not to mention the fact that Fedora 11 will go End-Of-Life [EOL] in about 2 weeks.).
I have a separate /home parition so I wasn't too worried about losing stuff, but I opted for an upgrade instead of a clean install. I backed up /etc just in case and dropped to runlevel 3 and ran the preupgrade-cli client that Fedora provides for upgrading. That process ran smoothly and it prompted me to reboot to being the upgrade.
After rebooting the kernel oops'd, but continued on to the upgrade procedure. In order for the upgrade to work properly I had to edit the GRUB boot line to force the installer to use text only. I attribute the oops and the required text-install to the fact that my Dell Optiplex 755 workstation uses an ATI RV610/HD2400 video card. I've found that ATI cards are not so Linux/Fedora-friendly.
Once in text mode there were some odd characters displayed on the screen but the upgrade proceeded as expected. Again, I chalk these up to ATI jankiness.
After the upgrade completed I rebooted and was surprised to see that Fedora loaded open source radeon xorg driver, detected and configured my dual displays properly. After logging and fixing some nss_ldap TLS issues I found that 3D acceleration and compiz-fusion actually works with the open source radeon driver now. Excellent!
All-in-all, the upgrade process was fairly smooth, and I give Fedora 13 a positive review.
If you are a Fedora user, F13 is a definite upgrade in my book. If you're not a Fedora user, you should download the Live CD and check it out for yourself.