Ryan Seacrest is bringing out the big names for the second annual iHeart Radio Festival, set for Sept. 21-22 at the MGM Grand in Las Vegas. The 2012 lineup boasts a superstar roster featuring Pink, Rihanna and Taylor Swift — and that’s just the beginning.

The ‘American Idol‘ host unveiled the lineup this morning in a video announcement. “Last year, we introduced the world to the biggest live music event in radio history,” Seacrest said. “This year, the iHeart Radio Music Festival is back. It’ll be even more epic.”

Also on the bill are Lil Wayne, Usher, Pitbull, No Doubt, Calvin Harris, Enrique Iglesias, Swedish House Mafia, Green Day, Aerosmith, Shakira, and more. Both Pink and No Doubt have taken extended absences from touring — Pink to become a mom and No Doubt while the group was on hiatus — so the inclusion of those two acts makes the event even more of a hot ticket.

That’s an impressive way to follow-up last year’s inaugural iHeart Radio Festival roster, which featured Lady Gaga, Coldplay, David Guetta and Kelly Clarkson, among others.

Fans can purchase seats for the 2012 iHeart Radio Music Festival starting this Saturday at 1PM EST on Ticketmaster. In addition, participating radio stations across the country will be giving away all-expense paid trips to Las Vegas to some lucky listeners.

Watch Ryan Seacrest Announce the 2012 iHeart Radio Festival Lineup