While I am not as familiar with other types of music, I can say for sure rock has been tragically stymied over the last several years and the main culprit is PPM. Or, more fairly, how programmers have reacted to PPM. Since the programmers get much more detailed information nearly to the minute, programmers are now far less likely to try anything that may result in a tune-out by even a fraction of the audience, since the PPM will record the tune-out immediately.
In the old diary world, people wrote down what they thought they listened to, which was in many cases different from what they actually listened to. So when their favorite station played a "clunker" and they changed the station for a few minutes or even longer, they still dutifully wrote down their favorite station without, in many cases, even acknowledging the station they turned to. Therefore no harm no foul to their favorite station. But with every tune-out being recorded in real time in a PPM world, no programmer wants to take chances (the stakes are too high, the potential for failure in the form of tune-out is too high) so they play the same tired cuts by the same tired artists, that have been consultant-tested and approved for years.
Think of many of your favorite acts - would they be given a chance if they were just starting out in radio today? Most likely not. Would a quirky band like Talking Heads make it into rock radio playlists today? Not a chance. The programmers would say "Too weird, to nerdy". Yet they became a rock staple with many mega-hits and mega-selling albums. In 1977 they got a chance. In 2011, no way.
If I ran a rock radio station today, I would identify one new band every month and play the hell out of them: give them lots o' spins, talk 'em up, have them come by to do a local show that the station would sponsor, give them an hour on a Sunday night to spin the songs that influence them and talk directly to the audience. You get the idea. Actively promote them. You would only need to play them once every 3-4 hours, so tune-out would be minimized. You can still play Aerosmith, Skynrd, and the Cars (or the equivalent active rock artists) afterwards, but over the course of a year, the station would be solely responsible for breaking (or at least giving the opportunity of a big break to) 12 up-and-coming bands. At the end of the year, take the best single from each band and put 'em on a station sponsored CD (or album download, whatever) much like KFOG does, and promote the bands and your station at the same time.
Of course not all bands will hit, in fact most won't. But some will. In time a few will hit it monster-big. And the station will be able to claim them as their own "home-grown" band. This would build reputation and lasting goodwill which will make up for any short-term PPM tune-outs. How many bands did KROQ break back in the day? How many bands know that but for KROQ, they'd be working a record store counter (or worse) somewhere? But most importantly, how much goodwill did KROQ earn? The station continues to live off of a heritage it built 30 years ago even to this day.
Somewhere out there, there is another Bruce Springsteen playing the bars or the small clubs. It just takes a Jon Landau to find him. Or an Elton John, who just needs a Robert Hilburn in the audience. The rock stations who need new, fresh content should be playing that role. But they're not. They're quite content to cue up the next cut off of the tired old playlist and invest zero dollars into their product. That playlist, and their response to PPM, is what will kill them.
