I am currently reading an excellent book called "Killing Yourself to Live" where author Chuck Klosterman visits the sites of many famous rocknroll deaths including Elvis, Lynyrd Skynrd and Kurt Cobain. Klosterman is one of my favorite writers and all of his pieces for Spin are worth checking out.
As I spend my days building machines that can describe music, Klosterman's exposition on the meaninglessness of rock genres struck a chord with me. Researchers spend many hours and write many papers trying to classify genre, yet often most human listeners don't even understand these arbitrary terms. As a rock journalist, it's Chuck's job to help clear up this confusion! Here are a few examples of his wisdom:
SHOEGAZE: Music by artists who stare at their feet while performing—presumably because they are ashamed to be playing such shambolic music to an audience of weirdos.
PSYCH: (as in “psychedelic”) ... This is music for drug addicts, made by drug addicts.
IDM: This is an acronym for “Intelligent Dance Music.” Really. No, really. I’m serious. This is what they call it. Really.
So, even if your classifier can't tell "post rock" from "prog rock", now at least you have no excuse!