Well, it's not as bad as Jethro Tull beating out Metallica, but it's safe to say the Grammys got it wrong in the metal category again tonight. You see, comedy duo Tenacious D beat out Mastodon, Anthrax, Motorhead and Slipknot to win the Best Metal Performance award for their cover of Dio's 'The Last in Line.'

Now we love Tenacious D -- in fact, one of the biggest regrets in our history was not including 'Rize of the Fenix,' the best Who song of the past decade, on our 2012 Best Songs list. And their Dio bona fides are obviously legit. So, we hope they win four million comedy Grammys, if that's important to them. But this was the wrong call, and seemingly more proof that Grammy voters don't take heavy metal seriously enough.

Tonight's Grammy Awards show will feature live performances from AC/DC, Jeff Beck, Paul McCartney and a bunch of pop stars who will test the capabilities of our mute button. Here's our handy guide to what's worth watching and who you should root for.

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