Normally it's annoying to get a song stuck in your head. But if that tune happened to be from one of the year's biggest music sensations, it could be a sign that they're worthy of the title of E! Celeb of the Year, right?
The 16 stars in our Hitmakers bracket provided a killer soundtrack to 2011 and managed to grab some headlines as well while doing it.
So who's up against who?!
Beyoncé's grabbed the top seed thanks to a standout year: a successful album and a baby on the way! But being ranked No. 1 doesn't guarantee a win.
Could Selena Gomez dominate the tournament? Could Katy Perry's chart-topping success be enough for her to take the top spot? Or will Justin Bieber easily handle any competition thrown his way and march to victory?
Our latest NCAA-style bracket is all set (don't forget to vote in the other categories) and the biggest names in the biz are ready to play.
Plus, to show how much we love our stars, E! will donate $25,000 to the charity of the winner's choice.
Vote now for your fave!