The nominees for the 2011 Grammy Awards, which air live on CBS from Los Angeles on Feb. 12, were announced last night in the form of a live performance concert.

The Best Hard Rock Performance and Best Metal Performance categories were announced off-camera and the formerly separate categories have been combined into one, narrowing the margins significantly.

The nominees are listed below, and it's a mishmash of rock (Foo Fighters), metal (Dream Theater, Megadeth and Mastodon) and questionable (Sum 41.) We could argue about the genre parameters all day and all night, so let's move on, shall we?

The other "controversy" surrounding the nominations was regarding Van Halen. Rumors abounded that they would be playing the nominations concert alongside pop acts like Lady Gaga and Rihanna, but VH were a no show. There is also word that the legendary rockers might still actually perform at the actual Feb. 12 ceremony. No official statement has been released yet.

Recording Academy chairman Neil Portnow commented on the nominations concert, alluding to Van Halen being MIA, diplomatically telling HitFix that "What happened was very simple. In the world of creativity, everything is fluid. In the process of discussions that we had been having with an expectation that perhaps we would be at a point tonight where the artist involved and we, moving forward, would be ready to announce [a reunion], they weren't quite at that point. So it's live television, we go on to the next act. It's rock and roll and so on. That being said, we were genuine about the intention and we are genuine about the discussion."

Without further adieu, here are the nominees in the Best Hard Rock/Metal Performance category:

'Public Enemy No. 1,' Megadeth

'On the Backs Of Angels,' Dream Theater

'White Limo,' Foo Fighters

'Curl of the Burl,' Mastodon

'Blood In My Eyes,' Sum 41

Watch 'Backstage at the Grammy Nominations' Video