http://fedora.redhat.com/docs/udev/ has:
<Q>
Current Problems on Fedora
...
Nvidia
Quick solution: If you do not need rhgb, just load the nvidia module in /etc/rc.local
If you have udev >= 032-5, load the nvidia module:
cp -a /dev/nvidia* /etc/udev/devices
chown root.root /etc/udev/devices/nvidia*
The Bugzilla for this problem is 133900.
</Q>
According to Harald Hoyer, the author of the above web page, there is a chicken-and-egg problem with FC3, udev, and the nvidia drivers.
"The correct way would be to load the module from the X-server part and wait for the device nodes to show up. We expect the next steps from nvidia." (From an email.)
I don't know how nVidia feels about this.