Marrowgar -Frost
LDW - Frost What are you talking about ? the frostbolts in phase 2? dps should be interrupting them
Gunship -Fire (if your raid is dumb enough to stand in it) The fire damage is minimal and easily avoidable.
Saurfang - No resistance but you could pop AM w/ Devo at 30% if you wanted to
Festergut - Shadow heh
http://www.wowhead.com/?spell=72103 > aura mastery
Rotface - nothing here
Putricide - Shadow ( all of the p3 aoe raid damage is shadow damage) Tanks are getting 100x harder then the raid , them staying alive is more important then dps. You can down this boss if a few dps die but its a wipe if the tank dies.
Blood Prince Council - Fire for the orbs or Shadow for the Shadow Lance tank If your ranged tank has the correct ammount of orbs then he only gets hit for 3000 a hit and is easily healed threw the empowered shadowbolts.
BQ Lana'thel - Shadow x 100 million
Valithria Dreamwalker - Fire ( the real raid wiper is the Blazing Skeletons. uninteruptable fire damage) <- if your dps dosent kill the blazeing skeletons before they start that aoe then its your dps's fault.
Sindragosa - Frost damage x 100 million
Lich King - Shadow Shadow Frost Frost