You will probably need to import my PGP Public Key to verify that the package hasn’t been modified. This can be done by downloading my PGP Public Key, and running the following as root:
rpm –import bdpepple.asc
I talked to the GKrellM maintainer at RedHat, and it sounds like they will include this with a couple of other plugins in the next core release of Fedora.
Update: Removed rpm, since it’s been published in Fedora.us and Fedora Extras.