I was previously playing as Rogue but got tired of 45 minutes for random dungeons and not being able to use heavy armor . So recently I have started playing as Death Knight so that I could tank or DPS.
I already know about "Comprehensive Guide to Death Knight Tanking" by Satorri and am in the process of reading it but I was wondering what is the best talent spec for tanking whilst leveling at levels 60, 70 and up to 80?
I leveled my Death Knight back in 3.0.8? I pretty much ended checking and learning each specc as tank. Respecced more than daily. (almost duh)
Basic tanking talent build is 5/5/5 (least it was)
Everything else didnt matter. Thought, I enjoyed most unholy. If we had decent healer (most cases NO! I remember retridin, moonkin, shadow priest healing me. So ended up having Rune Tap or Unholy Blight when it was 51 talent of unholy tree. Then back in WotLK instances, I turned to Frost two-hander tank. Those were just sweet sweet times.
While used Rune Tap and unholy tree as leveling and soloing. (still thies were times when Dual Specc wasnt up?) My DK soloed Onyxia40 twice on ilvl200 gear, untill the nerf of Death Strike.
I tried the Blood spec to level, but as I wanted to level my DK to tank in the long haul, and I liked the look of the Frost tanking spec, I wound up switching from Blood to Frost and from 2-hander to dual-wielding around level 70. As far as people saying there is added downtime from needing to eat to replenish health, I rarely had a problem with that. Since I had plenty of tanking gear on, and liberally used Death Strike to keep myself healed, I only found myself needing to heal up after a fight if I had been AEing a half dozen or gotten chain adds one after the other up to around 10 or so. The most surprising thing I found was that I went from 750-ish DPS in Blood to 700-ish DPS in Frost- I barely lost any DPS at all.
I really think if you focus your gear on one aspect (either tanking or DPS), and pay attention to your surroundings/mobs/runes, any of the specs can work. I can't speak for Unholy since I did not try leveling with it, but Blood and Frost both performed perfectly well for me.
edit: I was assuming mostly soloing to level. I did some randoms, largely to complete quests in the dungeons to get some extra XP.