Though the more comprehensive overview of changes coming to the Death Knight class with the Cataclysm expansion won't arrive until tomorrow, Blizzard posted one of the biggest changes yesterday:

We're doing our Cataclysm preview on the death knight changes later this week, but we knew one change risked overshadowing all the others, so we figured we'd go ahead and drop the proverbial Blood bomb today.

In Cataclysm, death knights will have a dedicated tanking tree, much like the other three tank classes. That tree will be Blood.

We’ll go into more detail in the upcoming preview, but we wanted to take the opportunity to explain the reasoning for such a big change.

Why the about face? We actually thought the “tri tank” experiment worked out okay. We suspected there would always be a “best” tanking tree, because that’s the way these things shake out, but we hoped it would be close enough that many players could tank with their favorite tree. When we tried out this design for Wrath of the Lich King, we were using it as a test case to see if we wanted to do similar things with the warrior and paladin talent trees.

A lot has happened since that time. We introduced the dual-spec feature, allowing players to have a tanking spec and dps spec that they could switch between. We introduced Dungeon Finder, which makes it easier to find players who want to tank, and even let players level up using a dedicated tank spec. In Cataclysm, we are introducing the concept of passive talent tree bonuses and we think that feature is a lot stronger when the talent tree has a particular focus (such as damage, tanking or healing). For example, it’s safer to give more passive damage to a tanking tree than we can a dps tree. Above all, we were just spending a lot of effort trying to balance three trees (though it was really six trees, since each tree was trying to do two things).

It started to feel unfair to the other tank classes that we had to spend so much effort tweaking three types of DK tanks, and it even started to feel unfair to the DK that we couldn’t focus their tanking experience. One bit of feedback that really struck home was the DK players who said, essentially, “I look at the Protection tree and I’m jealous of all of the cool tools they have to help their tanking. As a DK, I have to pick and choose tanking talents from within a sea of dps talents.” Rather than have a strong focus, the trees felt a little watered down because they were trying to do so much. With Frost as a dual-wield, spell and runic power focused tree, Unholy as a disease and minion focused tree, and Blood as a self-healing, defensive cooldown, tanking tree, we think the focus of each tree is a lot clearer and cooler.

In Cataclysm, Blood will be the death knight version of a Protection tree. It will have passive talent tree bonuses that reflect tanking. It will have tools, such as a Demo Shout equivalent, necessary for tanking. Several of the more fun tanking talents from Frost and Unholy will be moved into Blood. We will be able to revise (or even remove) clunky mechanics like Rune Strike and focus on letting DKs generate threat with their normal Blood tanking rotation.

This is major change, and we understand it will be met with some disappointment from players who really liked the flexibility, those who appreciated the unorthodox talent tree design, or those few of you who really liked Blood dps. Nevertheless, we are convinced that this is the right change for the game.

More exciting death knight news coming up soon in the preview.