This just happened in the Phoenix via my fingers and brain. Go read it there, and the rest of the music coverage, because it's a total thing, including my man Michael's piece on South by South Wasted and the always hilar+tru Big Hurt column.
Talking about rock and dance music as if they were entirely separate entities is weird, because in the early years, they were essentially the same thing. In fact, dancing is one of the only two real reasons for music to exist; the other is to let everyone know you're better than they are. Music is also for making babies. Okay, so three things.
When rock and roll was invented, it would have been ridiculous not to dance to it — kids weren't stroking their chin whiskers and pontificating over Chuck Berry lyrics. But in the intervening decades, popular music has fragmented into a thousand shards of specificity, to the point where we're now approaching a 1:1 ratio of genre to listener. That means people who don't want to dance — most likely serious-minded indie pussies too cool to sweat — don't have to. Occasionally, a movement or a band comes along that makes it harder to resist. New wave and post-punk in the '80s, Madchester and big break-beat DJs in the '90s, and the DFA scene in the 2000s all worked their hypnotic beat charms on the kids. But though the marriage of indie and dance scenes is a recurring motif, it tends to come in short-lived bursts. Trends in music are cyclical, of course, so as soon as everyone starts dancing, it's time for the next shift of bands to punch in to work and take us in the opposite direction. That's known as the musical-spite corollary, a famous concept I just invented.
The back-and-forth may be over for this cycle, because if there's one thing music fans don't want to do anymore this decade, it's stand in a room and watch people play instruments. They want to dance. Thank the Australian electro-pop/whatever outfit Cut Copy.