Growing up in the Washington DC area back in the 70's, I would listen to WPGC and others...and yes, I always listened to Casey Kasem's American Top 40 Countdown.  On the web, ABC News is reporting that Mr. Kasem's last countdown has been completed.  I believe it was 4 or 5 years ago that Ryan Seacrest took over the countdown (AT 40), but Mr. Kasem has officially counted down for the final time.  He actually started the program in 1970!