Has KDE 4 caught up with KDE 3 yet?

Hmmm... I'm unsure if the reasons behind the one-process thing have been documented somewhere, couldn't find something quickly. If you want you could ask on #plasma (freenode) and see if anyone knows - maybe there are indeed possibilities and if you can argue a good case I'm sure the plasma devs would listen... I suspect it wouldn't even be that hard to write a proof-of-concept, and for that I'm SURE the devs would support you...

Again, I can't really argue about this, but I certainly would appreciate a more stable Plasma so if you could find it in your hart to put in the effort to make it possible, my blessing is yours ;-)