So apparently someone on the Mayhem Fest boards, who pretty much had the lineup correct the past two years, said that this would be the line-up next year.
Main Stage:
Rob Zombie
Five Finger Death Punch (ugh, not this band again
)
Lamb of God
Rotating:
Bullet For My Valentine (see FFDP)
Hatebreed
Cannibal Corpse
Side Stage Bands:
In This Moment (see FFDP and BFMV)
Devildriver
The Agonist
Job For A Cowboy
Gojira
Goatwhore
As usual, take it with a grain of salt