I downloaded Car Dock v2 from the market and am pretty happy with it as a replacement for the Car Cradle app loaded on the phone. Hopefully this helps until we can remap Car Cradle. Car Dock v2 allows you to pick the apps to view.
Does any body think this could be as simple as renaming google maps to whatever vz navigation is called? If the car dock app calls vzmaps.apk(or whatever it's called), can we rename googlenav.apk(or whatever it's called) to vzmaps.apk and maybe it will launch what we want?