I took the plunge and installed Kubuntu PPC on my old mostly unused G3 Powerbook this afternoon and it went pretty smoothly. I’m now in the process of poking around the environment and getting a better feel for things. Kynaptic makes adding packages totally easy and I’ve already added a couple games and other random doodads that aren’t installed by default. KDE does seem to have a display bug where window titles get a little screwed up, but it seems to be mainly an aesthetic issue. I’m really impressed in general with the level of integration and functionality you get when you use KDE. For a reasonably skilled computer user this is a totally viable free alternative to the Windows (and Macintosh) world.
Linux on the PPC platform has come a long ways since I first started playing with it 6 or 7 years ago. Installing Linux on Macs used to required special floppy boot diskettes and a lot of crazy hoop jumping, but no more. In fact from what I can tell the Linux PPC releases are basically simultaneous and on par with the Linux i386 releases in the Ubuntu/Kubuntu world. Progress is pretty darn cool.