LL Cool J
Metallica to perform with pianist Lang Lang
Performance will be the country singer's first at the awards
Lorde also added to show, which will air this Friday
The top five artists chosen by you will comprise a fan's ballot
Voting is again open to fans
On the scene with Ke$ha, Miley Cyrus, Pitbull and more at the iHeartRadio Ultimate Pool Party in Miami Beach
See images from the MC's family-friendly rap guide
Jay-Z and Justin Timberlake, Paul McCartney, Beyonce and more tours you don't want to miss
'The song did its job,' the rapper says on 'The Tonight Show'
Singer explains idea the behind the song on 'The Tonight Show'
Questlove, Conan O'Brien, Judd Apatow and more react to Brad Paisley and LL Cool J's controversial song
Second collaboration follows 'Accidental Racist'
Rapper is proud of controversial song with Brad Paisley
'I wouldn't change a thing,' country star says of new album