There's a lot of godawful dubstep (I'm looking at you and your Grammys, Skrillex). Hex nailed it: the guy's songwriting sucks. Some dubstep works in parts and then turns super-irritating (go to 1:28) at the drops.
Here's a piece I think works on all fronts. I'm seeing Bassnectar in a week and look forward to being the oldest person in the crowd.