I've now spent 30 days with KDE 4.1 on my home desktop, as well as on one of my office PCs - I downloaded Mandriva 2009 Live when it was released, installed it & what a pleasure.
Uwe was right, the new interface takes some getting used to, but once using it, it is really nice. So far, I've not had a single crash/bug in any application; everything just works, and works well
I didn't spend much time testing all the new the eye-candy though - the bits I did test really slowed my PC down, but this was expected.
Dolphin was the real surprise; it takes some getting used to, but especially the command-line session one can open below it I found of much value; I work on the command line quite a lot, and in combination with the visual browsing it is great; click-click to get to a directory, and type your commands
All in all a very pleasant experience, and one I can recommend.
The KDE team did a great job!
