WoW Blue Post (Classes Changes)

Death Knight
Blood Plague and HoT removal
This (the hot removal of Blood Plague) is something we are definitely taking a hard look at for 3.1. Plague Strike is intentionally weak because of this ancillary effect, but that also leads to death knights not wanting to use a core ability except when doing PvP against hot-based healers (which pretty much means druids). Death knights' survivability and utility in PvP are definitely not something we are overly worried about at the moment.
Rogue
An Overkill change would have required more redesign of the talents and abilities than we were willing to make for a small patch like this. We're also unconvinced it would have fixed the problem alone.
Basically, it might have helped stealth burst, but wouldn't have helped with unstealthed burst, which was still too high in our opinion. Two Mutilates and a Cold Blood Eviscerate within one Kidney Shot duration is a ton of damage, and is possible with unglyphed Vigor and no Overkill. Add a partner or an interrupt or whatever and it can mean death for most players in very few GCD.
Overkill and glyphed Vigor are something we will probably look at for 3.1, depending on how the current changes shake out.
Dirty Deeds / Mutilate bug
Rogue poison damage / Consequences of changes made to Mutilate
Rogue poison damage had at least two bugs in the system when Lich King launched. When we fixed those bugs, rogue damage dropped significantly. There is speculation that the same thing is true of Dirty Deeds -- that because Dirty Deeds was inflating poison damage more than we realized that rogue damage will drop too much with the Mutilate changes and Dirty Deeds bug fix.
We do not have that concern at this time. We are happy with Mutilate's extra damage to poisoned targets to be 20% with or without Dirty Deeds. We plan to increase rogue PvE damage in other ways, such as through the announced (but not finalized) Hunger for Blood,wow gold, Killing Spree and Lightning Reflexes changes in 3.1.
Whether the Mutilate change and Dirty Deeds hotfix will be the death knell for rogues in PvP, we will continue to pay attention on it.
Warlock
Using Voidwalker to tank raid content (Sartharion)
Voidwalker won't continue to be an excellent tank for challenging raid content.
The health boost was largely for PvP reasons and the damage avoidance was to make up for limitations in pet AI and master control, not to let you opt out of having to manage tons of incoming damage on your main tank.
Warrior
Tanking and disparities between classes
We still are not convinced that warrior tanks are operating at some huge deficit compared to other tanks. There are going to be situations where one or the other classes are going to feel easier as tanks,cheap wow gold, just because the abilities and mechanics are still different despite all of our homogenization (and we really don't want to homogenize any more).
Heroic Strike is definitely one of the best items for the warrior. It does its job in letting you convert excess rage to threat without consuming a global cooldown, but it requires a lot of extra button pushes. It is something we are discussing.