Griffo,
Skidmore has been reported as saying that ADSB for VFR would be wonderful. It was in Australian Flying I think in a story about the Enigma unit.
What is really needed for VFR as a Flarm with somewhat better range. Around 20nm is all you need for adequate warning of potential conflicting traffic. Even 10nm would do.
No interaction with the ATC system, hence no need for expensive super integrity monitored GPS, no pressure altitude required either. All the GPS receivers in a given small area will see the same signals and hence provide compatible solutions. Close range collision avoidance is interested in RELATIVE position not ABSOLUTE position like the ADSB system.