Originally Posted by Neto-

So, I spent some time fiddling with the spreadsheet (version 0.4.2) today and figured out the very best setup before Ulduar for Mutilate, for a JC/LW undead rogue, with pretty much all buffs, if anyone is interested.

Weapons: [Webbed Death] mainhand, [Webbed Death] offhand.
Ranged: [Envoy of Mortality]
Helm: [Valorous Bonescythe Helmet] Gems: [Relentless Earthsiege Diamond], [Delicate Dragon's Eye]
Neck: [Favor of the Dragon Queen] Gems: [Delicate Dragon's Eye]
Shoulder: [Valorous Bonescythe Pauldrons] Gems: [Delicate Scarlet Ruby]
Cloak: [Drape of the Deadly Foe]
Chest: [Chestguard of the Recluse] Gems: [Precise Scarlet Ruby]
Wrist: [Thrusting Bands]
Gloves: [Valorous Bonescythe Gauntlets] Gems: [Deadly Monarch Topaz]
Waist: [Stalk-Skin Belt] Gems: [Delicate Scarlet Ruby]
Legs: [Valorous Bonescythe Legplates] Gems: [Delicate Dragon's Eye], [Deadly Monarch Topaz]
Boots: [Footwraps of Vile Deceit] Gems: [Deadly Monarch Topaz]
Rings: [Surge Needle Ring] and [Ring of Invincibility]
Trinkets: [Darkmoon Card: Greatness] and [Fury of the Five Flights]

Things that might be interesting: 4-piece T7 blows any other gear combination out of the water. All the items suggested on the OP aren't too far off from the items I have listed here, but some of them are substantially behind, such as the [Dawnwalkers] and the [Belt of the Tortured]. Using one Expertise gem is actually better than one Attack Power gem for this setup, but using more than one Expertise gem or a [Precise Dragon's Eye] isn't worth it (first one would put you over the cap, and the second probably has to do with expertise rating rounding). The [Mirror of Truth] is behind [Fury of the Five Flights], but as Aldriana mentioned earlier, it's only better in a theoretical fight, as in, a fight that isn't interrupted. As most rogues will have both anyway, I recommend switching accordingly (Fury for stationary fights, Mirror for most interrupted fights).