Well, the Death Knight beta honeymoon is over. Blizzard spent the last two patches gutting the numbers on Death Knight DPS (along with many other classes), presumably so that they can get all the nerfs out of the way and let the news for the remainder of beta be buffs and other goodness. The results are, well, jaw-dropping for anyone who has been playing the class previously.
A greater role for autoattacks
One of my earliest posts regarding Death Knights pointed out that I was able to fight higher level mobs easily in part because my weapon skill and hit rating didn't matter; there are talent bonuses to the hit rate of special attacks, and runes regenerate whether or not my autoattacks miss (unlike a Warrior/Bear's rage bar). Well, autoattack damage is relatively similar to what it was (after all, Blizzard will be trying to balance all the melee DPS specs in the nearish future), which means that almost all of the nerfage came off of Death Knight special attacks.
After seeing this in action, I wish they'd gone the other way. My biggest complaint about the design of the original Paladin was that the class was about casting your seal and then AFK auto-attacking for a minute or so. The DK felt more interactive than other melee classes precisely because so much of its damage output came from active skills on the player's part rather than passively waiting for white damage to pile up. The Frost tree feels especially hard hit, not necessarily because it sucks, but rather because the whole point of the tree is to get a combo going for a large burst number. When the payoff for your combo is an unimpressive number, well, it makes you question why you went to the trouble.
Death (again?) to ghouls
As I've long maintained, one of my favorite aspects of the Death Knight is the Ghoul pet. Fighting side-by-side with your minion is a different mechanic from the true pet classes in WoW. The good news is that my little pets now get a random name each time I replace them, and the bug that prevented Unholy DK's from sacrificing their pets for health has finally been fixed. The bad news is that the little guy seems to be dying. Often.
Part of the problem is that I am struggling to hold aggro over my own pet. Most DK's are going to have at least some points in Blood, probably including threat reduction while in Blood Presence (the DK's DPS stance). Combine passive threat reduction with a drastic reduction in DPS and suddenly the little biting critter is pulling aggro off me. I'm not sure if he's actually squishier than before (I think he is, but the fact that I was killing mobs so quickly may have masked that), but I'm at the point where I'm messing with my spec to try and do a better job keeping the poor little guy (un-)alive. I suppose he is supposed to be expendable, but, as things currently stand, he dies so often that you're not going to get much use out of the little guy at all unless you spec for Night of the Dead.
Ironically, Unholy DK's now feel like they have more healing capacity than Blood DK's, thanks to frequent access to Death Pact and more diseases to proc off of Death Strike.
Picking up the pieces
Obviously, Blizzard had to do something to DK's in order to prevent them from being completely overpowered compared to other melee classes. This is not going to be easy, especially with the distracting patch 3.0 PTR presumably going live sometime in the next week. I just hope they can find a way to balance it without losing the balanced for awesome feel that the class had before they fixed it.