I came across this interesting article from MTVHive, 2011, The Year Dubstep Broke. That came out at the end of last year, but with Skrillex taking a couple of Grammys this year, it seems like dubstep stealthed onto the scene and everyone just noticed.
Vibrant music often incorporates new sounds and ideas without worrying too much about genre, so it's no surprise that electronic music is permeating pop and indie rock. At least a third of the bands I review have at least a toe in the electronic realm (it could easily be all of them if I let it).
Now, as that MTVHive article mentions, everyone from Britney Spears to Korn is jumping on the bandwagon. Some artists are just throwing in the iconic bass rumble, almost as a hipster reference. Others are outsourcing by partnering with established mixers.
But many people just confuse electronic for dubstep, especially if it's got a bass heavy wobble. The dubstep meme is a bit like glitter in the US. It can bedazzle anything to make it sound edgier. The worldwide electronic scene along with Americans in the know must be somewhat bemused by the sudden popularity. Or maybe they're horrified at their sound being coopted by newbies. Either way, dubstep gets to be the musical cilantro for a while until something else comes along.
Personally, I enjoy the intensity of dubstep and its cousins, but I tend to prefer it in its natural, live setting.