In Cataclysm, Blood will be the death knight version of a Protection tree. It will have passive talent tree bonuses that reflect its tanking role.
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…. 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.