Pgeofilter will scrub the Planet Geospatial front page of entries from a single blog. You will need to make one edit to the code to specify that blog. Note that with a little cut and paste you could hack this script to filter several blogs. Please note that this script is aimed at the mid-November incarnation of Planet Geospatial. I’m using it to filter out the echoes on Planet Geospatial; the blogs which simply link to each other without providing any original content.