I don't know if AC is "disappearing" as much as it is slowly becoming hot AC. Here in Nashville, we don't have a hot AC, but our AC is slowly becoming hot AC (except for during Christmas, of course, when they are as sappy as ever!
I tried to report WJXA to the site where I get my Arbitron ratings and the man claimed they were still soft AC. I had seen their playlist online and knew they weren't. And now I don't even know how to report errors because they took away that link and I lost the email address.
At least the guy changed WEZV Myrtle Beach, SC from soft AC to adult standards (even if the man who ran things there insisted his station was soft AC when it has more in common with Dial Global's America's Best Music). There's no way it was in the same category with WJXA or even WSPA, which I think was finally changed to AC.