Let’s use this thread to keep track of aircraft who have been re-registered. Here are a few:
N903AG is now N454AN
http://flightaware.com/live/flight/N903AG
http://flightaware.com/live/flight/N454AN
N555SR is now N404HR
http://flightaware.com/live/flight/N555SR
http://flightaware.com/live/flight/N404HR
C-FBLU is now N1127M.