Here's an interesting application from Google - GPicSync automatically inserts location in your photos metadata so they can also be used with any 'geocode aware' application like Picasa/Google Earth, Flickr, loc.alize.us, etc.
automatically geocode your photos (in the EXIF header)
use a GPS tracklog in the GPX format or NMEA format (multiple selection possible)
Support elevation data if present in the tracklog
create a Google Earth KML file to directly visualize the geocoded photos and track in Google Earth
create a Google Maps file to publish your pictures and track on the web
Automatically associate audio or video files in Google Earth and Google Maps
create a Google Earth KMZ file (containing your geolocalized pictures and tracklog).
add additional geonames and 'geotagged' metadata (for automatic tagging in Flickr for example) and create an automatic IPTC caption
manually write latitude/longitude in a picture EXIF or a selection of photos
handy tools integrated (Time correction tool, EXIF reader, GPX inspector, rename pictures with date/location,)
supports Jpeg pictures and main RAW files format