The festival, produced by Live Nation, will also feature Dragonforce [ tickets ] and Mastodon [ tickets ] on the main stage, along with a host of other acts on two other stages: Machine Head [ tickets ], Airbourne, Five Finger Death Punch [ tickets ] and Walls of Jericho [ tickets ] on the tour's Jagermeister Stage, and Underoath [ tickets ] news, tour dates, photos and tickets"> Underoath [ tickets ], Black Tide, Suicide Silence, The Red Chord and 36 Crazyfists on the Hot Topic Stage.

Co-headliners Slipknot plan on releasing their as-yet untitled fourth studio album sometime later this year. The anticipated effort would be the band's first CD of new material since 2004's "Vol. 3: (The Subliminal Verses)." The group has been on hiatus in recent years as members concentrated on various side projects, including lead singer Corey Taylor and guitarist Jim Root's participation in alt-metal act Stone Sour, and drummer Joey Jordison's stints with Korn and Ministry.

Disturbed will be supporting a new album, "Indestructible," which is scheduled to drop June 3. The self-produced set is the band's fourth studio album, following 2005's "Ten Thousand Fists."