This year's Grammy nominations have been announced and here are the relevant ones in Hard Rock and Heavy Metal:

Best Metal Performance
For solo, duo, group or collaborative performances, with vocals. Singles or Tracks only.

Lamb Of God - Redneck (Track from: Sacrament)

Mastodon - Colony Of Birchmen (Track from: Blood Mountain)

Ministry - Lies, Lies, Lies (Track from: Rio Grande Blood)

Slayer - Eyes Of The Insane (Track from: Christ Illusion)

Stone Sour - 30/30-150

Best Hard Rock Performance
For solo, duo, group or collaborative performances, with vocals. Singles or Tracks only.

Buckcherry - Crazy Bitch

Nine Inch Nails - Every Day Is Exactly The Same (Track from: With Teeth)

System Of A Down - Lonely Day (Track from: Hypnotize)

Tool - Vicarious (Track from: 10,000 Days)

Wolfmother - Woman (Track from: Wolfmother)

Joe Satriani was nominated for Super Colossal in the category of Best Rock Instrumental Performance (for solo, duo, group or collaborative performances, without vocals. Includes Rock, Hard Rock and Metal. Singles or Tracks only). Underoath was nominated for Best Short Form Music Video (For an individual track or single promotional clip.)

You can view the full list of 2006 Grammy nominations for all categories here:
http://www.grammy.com/GRAMMY_Awards/49th_Show/list.aspx#04