I'm giving KDE a shot with kubuntu-desktop. So far it seems pretty slick! The interface reminds me of SPORE.
Out of the box it is much more visually appealing than GNOME, and some of the feature seem kinda nifty. It seems they took some hints from Mac and Vista, where it seems like GNOME is still sticking it out with the minimalist idea.
Only problem so far: avant-window-navigator crapped out right away, but I just restarted it and it seems to work fine.
I'll post more on this later, maybe even give some tips on how to get things working under it if I run into problems.