Kpop
Every culture and country has their own type of music. In South Korea, there's a type of music called Korean Pop, also known as Kpop. Korean pop music wasn't very popular and was limited to only Korean people exploring this music. But soon, as other Asian countries were exposed to this kind of music it began to spread throughout the Asian countries. Korean stars did tours in Japan, Hong Kong, parts of China, and now America. A very popular girl group called Girls Generation (SNSD) has taken over the world of Kpop. SNSD is a group of 9 girls singing and dancing, doing a number of music videos and tours. They make the most money of all Kpop girl groups. But recently America discovered Psy who not only became very popular in Korea but also taken America by storm. He released a video called Gangnam Style that was ridiculously humorous that everyone had to love it. After a fetish with this song, it soon died out. He released another song called Gentleman but it was nothing compared to Gangnam Style.
Now, in Theory of Knowledge this could be considered Appeal to Popularity/Popular Belief. In a matter of fact, music seems to happen that way. When one person finds a song interesting and they like it, people tend to share the video. And because they have influenced the person to believe the video is good they tend to already have a liking to the song before hearing it because of positive review and feedback. It doesn't necessarily work like that with everyone, but it does in some cases. And when the video is introduced to a friend while it's already popular and on the radio, they might like it because a MAJORITY of the people already do. And if one chooses to not like the song, they might be considered "out of the loop".
http://www.youtube.com/watch?v=b41iRaS-CtE