Wow.
This article from the Boston Globe really brings it home.
We've all known for a few years now that AM Radio, as a medium, was slipping badly. Traditional cornerstones of AM formats...sports and talk...were losing market share, and several major AM signals were electing to simulcast on an FM station and seeing positive results. At the same time, we're also seeing a lot of traditional AM formats bypassing AM altogether and starting on FM, also with positive results.
One place near and dear to my heart where this has been playing out is Boston, where many, many years of market dominance by WEEI 850AM (sports) and WBZ 1030AM (news) are radically shifting. WBZ still has a killer signal; one of
the best AM signals in the USA, actually...famous for being heard in 38 states...and able to hurl almost 100,000 watts across an AM-friendly saltwater path right into Boston. Even so, WBZ has seen increasing competition from local (and national) NPR powerhouse WBUR and, more recently, WGBH's flip to mostly-NPR-news, too.
But it's WEEI that's the most eye-opening. After two years of losing substantial market share to upstart SportsHub 98.5 (aka WBZ-FM) despite WEEI having the Red Sox games...Entercom finally killed off Mike 93.7FM and simulcast WEEI on the 93.7 signal.