After some initial testing here are my thoughts on DK talents:
LvL 56 talents:
DW Frost - Plague Leech
2H Frost - Unholy Blight for AoE Cleave / Plague Leech for ST
Unholy - Unholy Blight
Blood - Unholy Blight
LvL 57 talents:
AMZ - too short at too low a reduction to be worth the talent point outside of VERY specific fights.
Lichborne - The switch to leech makes this talent pretty shitty for anything other than immuning the CC's it lists.
Purgatory - This is going to be the default for pretty much every spec
LvL 58 Talents:
Death's Advance - Needs to go baseline, DK's have enough mobility issues as is.
Chilblains - very situational, really painful to take over DA
Asphyxiate - Our only stun that actually works making it really valuable for PvP, but again really painful to take over DA.
LvL 60 talents:
DW Frost - Blood Tap (macro'd to FS)
2h Frost - Runic Corruption
Unholy - Blood Tap (macro'd to DC)
Blood - Runic Corruption
LvL 75 talents:
Death Pact - Pretty shitty now even with the removal of minion dependance.
Death Siphon - Still really strong for DW Master Frost/Unholy. Loss of Vengence makes is rather meh for Blood.
Conversion - Broken for normal dungeons/legacy content/PVP as Blood, worthless for raiding. May still have a use in PvP, but you will still need to sit in blood presence.
LvL 90 talents:
Remorseless Winter - Still shitty for PvP, Still doesn't work half the time in PvE.
Gorefiend's Grasp - Still useful in any fight with lots of adds and organized PvP.
Desecrated Ground - Pretty much PvP exclusive
LvL 100 Talents:
Necrotic Plague - Currently every spec should use this
Defile - Not bad, but Necrotic is still far better, the 10% damage reduction component is simply lackluster.
Breath of Sindragosa - DPS loss almost any way you cut it, healing from Marks of Sindragosa is almost completely worthless.