After the autoinstall completed (message said "...Successfully") and while re-booting, 2 error messages appeared:

Starting mythTV server: error while loading shared library: libXv.so.1. Cannot open. No such file or directory.

..and a few lines later:

Starting GNOME Display Manager: gdm/usr/bin/gdm: error loading shared library: libX11.so.6. Cannot open. No such file or directory.

I logged in as myself (not mythtv or root) and did a find / and sure enough they're not there. Did they not come over during the install or what?

Sounds like a bad burn or incompatible disk. Try rebooting from the CD and adding the "testcd" option to the boot command.