The West is definitely catching up to Korea, not just in terms of gameplay skills and popularity, but casting too. A fun exhibition League of Legends match between two pros at this weekend's IEM tournament in San Jose were casted by no less than six commentators. And, as you can see and hear above, this caused some chaos.
And why compare it to Korea? Check out an average Korean cast below from the Brood War era of StarCraft:
IEM commentators go Korean [YouTube]