One of the reasons Psy's 'Gangnam Style' has been so popular in the west is because he has a very specific personality type. That's rare in K-pop and in order for the scene to really hit the mainstream, artisits need to push that idea of celebrity a bit more.
Bands such as Shinee or Girls' Generation are kind of anonymous, whereas Psy or G-Dragon from Big Bang have emphasised personalities, and that's why they've managed to cross over. You can see this happening more and more though.
It's the insane art direction in K-pop music videos that got me addicted to it. I like the misguided appropriation of western pop tropes in the videos - because they've got it wrong, it's kind of better. You would never see someone with a weave 30ft long in a Western video, like at the beginning of Big Bang's 'Fantastic Baby'.
I've not been able to get to a show yet because there have only been a couple in North America, but it would be awesome to go and check it out. The acts I'm loving at the moment are Big Bang, f(x) and 2NE1.
Key Song: Psy - 'Gangnam Style'