This song and video are played on Taiwanese MTV a lot and I'm sure it's very popular in Korea as well. The girls kinda remind me of Girls Generation, they're just a bit more into street style and crazy fashion, while GG are obviously playing the seductive Lolita role, trying to appeal to older men. Music is not very different, if you ask me. The song 피노키오 Pinocchio (Danger) is catchy, but I wonder how long will it need for people to get sick of it. My guess is not too long.
Here are some live videos of f(x)'s Pinocchio (Danger):