Hmmmmm, I think this gotcha might have caught me too. I applied a bunch of updates last night (including an X.org one) and then when I logged in as a different user (restarting X in the process) my wireless mouse stopped working. I'll check my xorg.conf.
Asus Eee PC 901, 2GB RAM, 20GB SSD + 16GB SDHC w/ Fedora 11
HTC Hero w/ Android 1.5 (MoDaCo Custom ROM 2.2e)