I discovered this video after surfing Youtube for the 100 music videos and it was in the top 5. Out of curiousity, I viewed the video and was entertained throughout.
I find it hilarious in the comments especially from the Koreans trying to explain to the ignorant ones that it is not Japanese. I can imagine the association that might get some pissed off.
I recognise the girl in the video as Hyuna, a member of Korean K-Pop group 4Minute. I know her from the super hot video clip below for the song Bubble Pop.
Besides this video going viral, K-Pop have certainly gone international with Wonder Girls, 2NE1, Bing Bang, Super Junior, Girls Generation among many others getting huge success internationally.