No, I didn't have hostip installed - that did it. I assume that the script needs to be run from the directory containing the poi.db file (at least that's where I ran it). Worked like a charm.
I tried installing gpsd and the geoclue gpsd backend, but that seems pretty broken at the moment. It would be a nice option though, as I'm not sure the hostip backend would populate correctly if I'm using a EDGE connection from T-Mobile (but I haven't tested that theory).