You know you're no longer a rookie when you get a Grammy nod - even if it's for best new artist. And when you get five nominations - putting you just behind the likes of Adele and Bruno Mars - you know your sound has moved firmly up from the underground. That's the case for dubstep producer Skrillex. True, the 24-year-old has been making noise for a few years now. But 2012 might be the moment his music finally hits the mainstream. Herewith, a look at a beat on the rise.