If you want to use KDE 4.4 on Fedora but do not want to upgrade to Rawhide (it is not even Alpha yet), here is an easy way to upgrade your KDE version to 4.4 while on Fedora 12.
The KDE packaging project is providing 4.4 packages for Fedora users. You just need to add their repository to your Software Sources in PackageKit. Here is how:
1. Go to the site and get the repo file under yum section. It is present on the home page if you scroll down.
2. Place the repo file you downloaded in /etc/yum.repos.d directory.
3. Go to KPackageKit –> Settings and enable the kde and kde-testing repositories. KDE 4.4 is present in the testing repository.
4. Open Konsole, and type: su -c ‘yum groupupdate kde-desktop’
After updating, restart to see shiny new KDE 4.4. 
Rex Dieter
13 Feb 10 at 2:36 am
kde-4.4.0 is in the kde-testing repo now, so I’d recommend using only that now. -unstable still contains a bit of stuff not suitable for the average joe user (ie, if using that repo, one should be able to manage things breaking from time to time).
Manas
13 Feb 10 at 11:25 am
Thanks for the update Rex.
I have updated the post now.
bas89
15 Feb 10 at 10:27 pm
Great
Thanks 
–
an happy Fedora user