Mac Miller: 21 Under 21 (2012)
Mac Miller: 21 Under 21 (2012)

No. 5: Mac Miller

Last Year's Rank: 6

Birthdate: January 19, 1992 (age 20)

Why He's Hot: After Mac Miller enjoyed a breakout year in 2011 when his album, "Blue Slide Park," debuted at No. 1 on the Billboard 200 chart, the Pittsburgh rapper continued his upward trajectory in 2012. The MC just finished the Under the InfluenceTour alongside Wiz Khalifa, and recently, Miller embarked on the second leg of 'The Macadelic Tour' in support of his 2012 "Macadelic" mixtape. While rocking major crowds, Mac is finishing up two projects simultaneously: his collaborative album "Pink Slime" with Pharrell Williams and his solo follow-up to "Blue Slide Park." In short, the lovable rapper's final year on our 21 Under 21 list was a resounding success.

Video Below: Mac Miller's "Blue Slide Park" Track By Track

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