13-year-old Beats Guitar Hero »

There was a pretty good South Park episode that covered the nonsensitudes of this phenomena.

My only real life observation is that the existence of this game in try-out mode in some electronics stores causes me to spend far less time in them, since they have the sound on the monitors turned down you mostly hear someone banging away on a piece of plastic (and usually not as in-time with any sort of music as this guy).