Whats Spec is best for Death knight?/

[Discipline]

Lol dude frost is tanking.

Lol dude you know nothing.

[Gfexgfx]

Killing machine in forst is one of best dps talent...

[Teh Megazord]

Lol dude frost is tanking.

Frostmoron--A misinformed miscreant that insists Frost is the only Death Knight tanking spec.

[never103]

Blood for all the DPS or holy for the summons and DOT's

[Gfexgfx]

Today i respec to frost/uh build (frost to HB, rest in uh) Thats great dps build, if u keep good rotation u can to +3500dps in decent eq

[GamleErik]

Im speaking with expirience of a 80 DK, i have tanked allmost whole Naxx25 (only missing Thadd before Saph and Kel), Maly10, Sarth10/25 etc. and tried to DPS in a few occations.

I have to say that DW Frost (to HB) and rest UH is by far the best DPS spec and tops my damage meters in raids (yes, at the very top). But again, this is dependent on hit gear, so if you are low on hit, dont go for it just yet.

If you are doing HCs, i would say UH will be good because of good AoE damage, and pretty good single target DPS also. UH also bypasses Blood in DPS in raids, so blood is best for soloing stuff.
If you are going UH, dont get any tank-oriented talents (Imp. AMS and AMZ). Corpse Explotion is also worthless (atleast untill the next patch hits). There might also be no real need to get Unholy Blight, and you should rather go down Blood after you have gotten all the UH talents you want. It would be something like this: Talent Calculator - World of Warcraft

Blood has allways been the worst specc DPS wise in my guild.

You also want Glyph of Scourge Strike
Basic rotation: (Single Target)
PS-IT-SS-BS-BS-RPdump-SS-SS-SS-RPdump(Gargoyle/Death Coil - Dont use Death Coil if your Gargoyle is up!)
(Change out one SS if your diseases go out)

AoE Rotation:
DnD-PS-IT-Pest-RPdump will get you the most DPS, even though you might want to stick with single target DPS unless there are like 5-6 mobs there.

[Gfexgfx]

I'm reading nice guide about pvp dk, maybe anyone want
Skribs' PvP DK Handbook - Death Knight - Wowhead Forums

[Cenimap]

Unholy ftw =)

[perza]

I kinda disagree on that blood is good endgame dps.
Maybe with the HS-OB build but otherwise stick to either 0/32/39 (DW) or
3/50/18 (DW) for burst and extreme aoe crits. The selfhealing problem is solved with casting raise dead and then death pact.

[Efidol]

unholy by far