Huh. I've really had my fill of Gnome 3. I'm an xmonad user, and the new shell's addition has only complicated my situation --- all the code that was taken out (for, say, customization of gnome's look & feel) was useful to me, and the new code (the shell) isn't useful to me at all.
If KDE's stable, it may be time for me to have a look. I just use chrome, emacs, a shell, and a file manager anwyays.
Since switching to dwm, I can't even remember what I used a desktop environment for (I went from KDE to Gnome to XFCE to (black|flux)box to dwm). Based on your usage, I'm surprised you'd consider leaving xmonad for something as alien as KDE4. Give me the speed and screen real estate of a tiling window manager any day.
If KDE's stable, it may be time for me to have a look. I just use chrome, emacs, a shell, and a file manager anwyays.