Michael Jackson's 40 year career is pretty darn impressive, but it's even more impressive when the Pentatonix sing the ultimate acapella MJ mash up in under six minutes.
December is the time when we wrap up the year and take a look back. Every year, DJ Earworm puts together a video mashup that sums up the year in music, and he has just released his ‘United State of Pop (World Go Boom)’ for 2011.
Besides Katy Perry and Rihanna, the mix features people like Adele, LMFAO, Lady Gaga, and other pop stars of the past year (but no Bieber!)