Tried it out on a live CD.

I thought it was really cool.
Has a lot of nice features and is supposedly
faster than previous KDE. Again I was using
a live CD, so I could not fully test the
speed/responsiveness. Response speed is
what made me change over to Xubuntu on laptop
and Linux Mint (also XFCE) on my IBM desktop.

In KDE4, the "big/tall" bottom taskbar will be resizable
in upcoming releases (heard that on the
<a href="http://www.linuxactionshow.com/?p=163">Linux Action
Show podcast Episode 70</a> ).

KDE reminds me of VISTA- kinda turns my stomach.
It also slowed down my FOLDING distributed processing TASK.

I installed KDE4 and with a bit of help on the Kubuntu forum am very
happy with it. There is another problem I'm having and have posted that
on the Kubuntu forum as well because as you noted there isn't a Kubuntu
forum. This Ubuntu forum is VERY helpful.

So is the kubuntu forum!
http://kubuntuforums.net/forums/index.php

I use it and it works just fine and is easier for those changing from
Windows in MHO