I think Suicide Silence will do Mayhem this year. This is given that some of the other bands on the cancelled Mayhem Fest cruise are confirmed (Hatebreed) or strongly rumoured (LoG).
I am not sure how much BFMV would draw in terms of crowds, haven't heard anything about these guys since like 2010. I would like to see something like: A7X, Zombie, LoG.
04/05 - Kataklysm, Aborted
04/08 - Carcass, Gorguts, TBDM
04/23 - Behemoth
04/24 - Nile