KIIS FM in Los Angeles has revealed the lineup for its annual Wango Tango concert, which this year features a star-studded roster with Nicki Minaj, Maroon 5, Pitbull, Foster the People, the Wanted, Gym Class Heroes and more. Also in attendance, though not performing, will be Justin Bieber, who will introduce his record label signee, Carly Rae Jepsen.

Ryan Seacrest announced the lineup this morning for the May 12 event. Also on the bill are hip-hop stars B.o.B, J. Cole, Big Sean, Wiz Khalifa, K'Naan, Chiddy Bang, Wallpaper and Diggy Simmons. That a lot of talent for a one-day event!

Pitbull told Seacrest, "Wango Tango's been a huge, huge part of my career. The beautiful thing is you've got so many people and so many different people."

Bieber may be the biggest star of them all, even if his only appearance will be in a guest hosting role to support Jepsen, the 'Canadian Idol' alum who is working on an album for U.S. release. The 2012 Wango Tango event takes place at the Home Depot Center on May 12. Tickets go on sale March 31 for the general public, with a VIP pre-sale the day before.