Ok, got it. Looks like it's working. Yum is still downloading it.
Scratch that. I just got an error:
Error: failure: kernel-module-nvidia-2.6.12-1.1378_FC3-1.0.7676-0.lvn.3.3.x86_64.rpm from livna-stable: [Errno 256] No more mirrors to try.
I know what that one means, and it's not good, but it means I'm doing it right, right?