Protoss Soup for the Korean Seoul

Earlier today, my friend Richard Yum posted a Tweet saying that Starcraft 2 sold 3 million copies last month and that he "bet like 90% of those were sold in Korea." Its a smart bet for Richard if history is anything to go by. According to the infographic below, 50% of copies of the first Starcraft were sold to South Koreans, but that was ten-years ago. Since then, interest in the franchise has exploded: Online Schools - Starcraft

I've never played Starcraft - how good is it?