After much speculation, the lineup to this Summer’s Mayhem Fest has been revealed. While Mayhem Fest will make an official announcement later today, our buds at Metal Injection have already let this year’s lineup slip. And pretty much, all of the rumors that spread around the web these past few weeks have have turned out true.

On the mainstage will be Slipknot (whose involvement pretty much slipped yesterday, not to mention via an anonymous tip we got last year), Slayer, and Motörhead. Playing on the side stages will be Anthrax, As I Lay Dying (who also let it slip early via tweet last night), The Devil Wears Prada, Asking Alexandria, Whitechapel, High On Fire, and a local band chosen at each stop.

However, some sources like Boise’s 100.3 The X, have not included Motörhead’s name, but do claim that a  “huge” headliner to be announced on March 5. It would make lots of sense if Lemmy and company won’t be officially announced till a later point since they’ll be taking part in Gigantour, which kicks off tomorrow (January 26) in Camden, NJ. Plus, we would be really surprised if Anthrax wasn’t on the main stage.

Regardless, this is a pretty sick lineup, and arguably the best one Mayhem Fest has had in a long time. Anyone else as excited as we are about this year’s tour? You can check out the entire rundown of dates for Mayhem Fest 2012 here.

Update: We just received an official press release confirming this year’s lineup. While Motörhead’s name is not mentioned, the release does say that a special guest will be announced on March 5 (as Boise’s 100.3 The X claimed). Thus, it’s a safe bet that Motörhead will be on the bill. Also, Anthrax will be headlining the “upgraded” Jagermeister Stage. As I Lay Dying, The Devil Wears Prada, and Asking Alexandria will be rotating slots on the main and side stages, while Whitechapel and High On Fire will be on the Jagermeister Stage.

Update 2: Still need more confirmation? Mayhem Fest have now confirmed the above information on their website.