After seeing my post about importing or searching GCFilms data from within Tellico, the lead developer, Tian, emailed me to say that he'd just recently added plugins for GCFilms to import and export Tellico data. That's great! Interoperability is always a good thing.
To test the GCFilms capability, you'll need to download the current CVS version, but I figure it'll be in the next release. As for Tellico, since I'm about to release 1.0, I'm in a self-imposed string freeze. As soon as that's done, I'll add the GCFilms import and export inside the app itself.