I tried to run KDE 4. It is nice looking, but just lacking features that used to be there in 3.5. The package manager is lame, Synaptic is better. The network configuration simply doesn't work, the Gnome Network Manager works well. The clock doesn't fit in it's allocated space, the first digit is hidden behind whatever is to the left of the clock. The last straw was Amarok. Version 2 totally sucks. I went ahead and installed Gnome, and it runs just as expected. It's still not as configurable as KDE 3.5, but it is more stable and the pieces fit and the pieces work. I installed Exaile to replace Amarok. It is nice and although it's a little unstable, it beats the abomination that Amarok has become.
I didn't make this decision lightly. I've used KDE for about 10 years, and instead of getting better, version 4 is worse. It's a good thing there are alternatives.