Following a recent upgrade, Xorg was apparently also updated to version xorg-x11-server-Xorg-1.6.1.901-1.fc11.i586 which unfortunately didn’t play nicely with version xorg-x11-drv-ati-6.12.2-14.fc11.i586 .  After a brief investigation, the combination resulted in this error:
 /usr/lib/xorg/modules/drivers//radeon_drv.so: undefined symbol: DRIOpenDRMMaster
Ultimately, this had the following effect:

No GUI (System never got as far as showing any graphics let alone KDE, Gnome etc)
No Keyboard [...]