The song is designed for the Asian market, if it has any success in the US then that's a bonus.
Here's the first live performance:
http://www.youtube.com/watch?feature=player_embedded&v=bQrbunVuka8
I like the song better live - you get to see all the dance moves. K-Pop songs also always have fan chants added to allow for greater audience participation.
The K-Pop artist will usually release the song, then MV, then hit the weekly Korean music show circuit (Music Core, Music Bank, Inkigayo, etc...) and peform live stages. (Similar to the old Solid Gold, American Bandstand, Club MTV, Soul Train, etc...) So, each song also needs stage choreography. The artists/idols compete against each other (via digital sales I think?) and a winner is announced at the end of each show.