CRAIGSTANTONNZ  You were just a few days early. The new version (2.0) does work with Leopard and iPhoto '08  
(Version 2.0)

CRAIGSTANTONNZ  I tried using some photos that I thought were geotagged but weren't. The program didn't complain and put out a geotagged.kmz, but with no kml so GE didn't like it. I suggest putting up an alert if non-tagged photos are used.

and one more thing. "West Latitude"? I've checked and it works with southern latitudes and western longitudes.  
(Version 1.3)

CRAIGSTANTONNZ  Version 1.03 has come out and it fixes some issues seen in Nikon's geotagging. MacUpdate should get the update soon in the mean time you can get it straight from my site. In the future you're better off emailing me with problems, I don't read this site very often so I've only just noticed your comment 2 months after it got posted  
(Version 1.0.2)

CRAIGSTANTON  why not use exiv2? It does the job just fine, and I was able to get help in compiling it into one binary I could include in the app.  
(Version 1.01)

CRAIGSTANTON  I just added Intel support in version 0.9. Please check it out and let me know if there are any problems.  
(Version 0.9)