I personally dislike KDE 4 as a GUI, but with my Debian hat on, I’m building official Debian/m68k packages. That they run merely shows that all the recent bugfixes (including the Linux kernel one that went into 3.2.35, thanks again bwh for all the accomodating) were good for something.
I’m building with Debian-Ports¹ gcc-4.6, which is just much more tested and somewhat bugfixed than Debian gcc-4.7 (and Debian gcc-4.4 which works well too though), but all three are available. GCC upstream is pretty active, although usually on the Coldfire side of m68k from Mikael Petterson, and Andreas Schwab is dealing with eglibc in addition to the toolchain and usually our rescuer.
① Debian-Ports because it’s a build containing patches not in unstable yet, and unlikely to go in before wheezy’s out: a backport of gcc-trunk (or 4.7)’s atomic builtins – used by Qt4 – and a port to FreeMiNT, among others.