I finally have a Linux-only solution for downloading and analyzing data recorded by my GPSMap 60Cx. No more messing with VMware/VirtualBox, Windows XP, Wine and Garmin's MapSource, having to wait a good few minutes just to retrieve a few bytes of data from the GPS unit.
I use GPSBabel to download tracks and waypoints from the GPS unit, I then upload the data to Garmin Connect for visualization and analysis. Garmin Connect is not without fault but it gets the job done.
My latest bike trip shown on Garmin Connect
Track shown in GoogleEarth