I'm running Fedora 9, and I rebooted this morning for the first time in a while. Boot process was normal, but when gdm came up, I was unable to use my keyboard to input my password.
Ctrl-Alt-F1 worked fine and the keyboard worked fine under the terminal. Reboots, killing gdm, etc did not work.
I finally used 'system-config-display --reconfig' as root and the keyboard resumed normal operation.
I suspect this is a timing issue with upstart based on:
Hope this helps someone else out there!