Well, I've been running KDE4 in various forms over the last few months, and I have some comments about the current state of the KDE4 entry in Rawhide (which is likely going to be the one in Fedora 9)...

1)  Um, with the exception of Fedora, every version of KDE4 I've seen now has an option for Plasma Theme in Configure Desktop.  Would it be too much work to port it here?
2)  Interestingly, Fedora's version of KDE4 seems to be the only one where the size option of the panels seems to actually be respected; even in KDE's own repository, this didn't seem to be the case until recently.  That makes me very happy, as I'm a stickler for small details like this, but that's a small opinion...
3)  XSettings-KDE.  Is there going to be any work on getting this to work with KDE4?  I do notice that KDE3 apps listen to it (at least, that's my feeling), but GTK apps don't seem to do the same...
4)  Is there a reason Nepomuk is left out?  Just asking.
5)  I'm going to have to suggest, after a couple of months, that it might be an idea to switch the window manager to something other than KWin temporarily.  KWin is horribly unstable as-is, and I believe it also leaks memory periodically (I've had cases where KWin steals 80+% of the system resources and no other program can get at them at all).  Personally, I stopped using it and adjusted KDE's windows to use Metacity instead, just for now.