I started writing a review of Fedora 12 a while ago but put it on the back burner as things came up... thinking the longer I wait to finish it, the more time I will have had with it... the more complete of a review I can do.
I don't really recommend upgrading to anyone... except under certain conditions. On servers where the package count is fairly low and the possibility of third-party addon packages is low, upgrading has been painless for me for the last 5 or 6 releases I've been doing them.
On desktops where there is a large number of packages as well as a greater potential for third-party packages to be installed (think RPM Fusion for certain verboten media codecs and apps)... I don't upgrade.
But Scott, aren't you crazy to do a fresh install rather than upgrade? Umm, no. I build my own remix each release... which ends up being a 1.9GB LiveDVD. It has all of the software I want installed and I update it periodically so it has all of the updates. I keep my /home directory (which is encrypted on my laptop/netbook machines) a separate partition and it saves all of the data I care about between releases... like a backup of /etc and /root... and anything else desired.
Sure it takes a while to prepare the build environment by downloading everything and then actually building it... but Fedora has made it fairly easy and pain free and it has worked well for me the last few releases. And all of that work can be done while my upgrade target machines continue to run. I do the building inside of a KVM virtual machine so it doesn't disrupt the host machine much at all.
Once I have the LiveDVD iso I turn it into a LiveUSB with Fedora's livecd-iso-to-disk script. Oddly a fresh install from LiveUSB media takes between 5 - 10 minutes depending on the speed of the hardware. That is a *LOT* faster than an upgrade (even if you use pre-upgrade) and everything works... and there is (almost) no kruft left behind from one or more previous releases to confuse newer packages. Granted changes in desktop environment releases and individual apps... that look for settings in your home directory... can accumulate some kruft BUT given the fact that Fedora does so much updating during their short lifecycle, keeping my target machines updated makes them have the same versions available in the new release (sometimes slightly older and sometimes even newer depending on how long I waited to do the install) that kruft building in personal settings is less likely. Oh, I said faster, right? :) How much faster? On machines with a ton of packages... I can do 5-8 fresh installs faster than I can upgrade a single machine.
For those who don't have a separate /home or who have a really good reason for doing an upgrade (not sure there are any but just because you can is always there)... go for it... but that isn't the only thing to care about in a new release... how well the upgrade works. While Fedora continues to try and improve the upgrade experience, I've just gotten used to doing it this way.
I don't recommend everyone do it my way... especially if you only have one or two machines to upgrade... but if you have 5 or more and you want the challenge and fun... why not try making your own remix with the stuff you want there and upgraded? It makes new machine installs and setups take like 5 minutes post install.
Now having said all of that... I rarely disagree with Mr. Jon Corbet but him discounting all of the new features of a new release and concentrating completely on the upgrade experience seems silly... unless he was just trying to make his review different from others. Umm, excuse me, new features do count... and in Fedora 12 there are quite a few worth noting. I'll not bother to note them here because this comment is already become a chapter.
Regarding the graphics issues... I'm guessing that while there have been some regressions... those are probably fairly common among all distros based on the same package versions Fedora 12 uses. There was a lot of noise regarding graphic card issues and Ubuntu 9.10. I have no solid data as proof but my personal experience has been that Fedora 12 provides many more graphics improvements for a wider range of hardware than the number of regressions. I tested it on about 10 different computer models (7 were Dells) and the graphics worked as well or better than in previous releases... supporting more features. That includes my Acer Aspire One D150 netbook. I guess I was just lucky given the number of computers I tried it on. My point here is that the graphics issues and/or regressions are less of a Fedora specific issue and more of a general upstream issue that affects many distros.
If someone wants to switch from Fedora to something else, by all means, go for it... have fun... but for me I'm sticking with Fedora... on my personal desktops anyway. I'll just be quiet about servers for now. :)