Sorry, should have been clearer. The fine folks who complied all of this data and are kindly sharing it free of charge only have it easily to hand in these 3 formats. They are set up primarily to support Garmin units, so everything is geared to generating Garmin .img files. (This is a full set of autorouting maps of New Zealand, by the way, not just POIs. I have seen their stuff working on a Garmin Nuvi unit, it works great, and is a wonderful alternative to paying $300 for Garmin's NZ maps!).

It looks like there are at least a couple of Maemo programs in the works that might have direct support for Garmin files, and that would be pretty cool too. But Maemo Mapper works now, and the ability to swap among different map repositories gives it a "wow" factor that vector-based apps do not currently support.

I'm not knocking GPSBabel. The concept of a "swiss army knife" program for POIs is sorely needed, and it supports a LOT of formats. But, alas, it could not do what I required!