The Way Of The Future would seem to be position determined in over-ocean planes by GPS, and position reports relayed by satellite to ATC.
Please correct me, but I understand that in Alaska, outside the range of ground radars/ATC, there is a scheme using beacons in each plane which report GPS location. The system in planes also listens for beacon position reports and produces a fake "radar" display showing the position of all cooperating aircraft within VHF range.
SC