World of Warcraft Classes Dissected at WWI

One would almost forget Blizzard's Worldwide Invitational event is also showcasing a lot of content from World of Warcraft. Joystiq has put up a handy overview of every class in World of Warcraft, including a whole lot of new info on the Death Knight.
We knew previously that DKs use runes for their abilities. Today we learned that they will have a 10 second cooldown. The short cooldown is meant to illustrate how the Lich King is able to command literal Armies of Undead. This prospect sounds awesome. I seriously want armies of undead at my disposal, like a wall of rotting flesh hurling itself at my enemies! I wonder how tough these dudes will be?

In terms of what role the Death Knights will play in battle, the developers said they didn't want to punish the player based on what spec they choose. Even though it's problematic for designers, they are sensitive to WoW's tank shortage problem. They want to avoid forcing DKs to choose between tank spec or DPS spec. They are searching for a more flexible solution to the problem, giving a player as many options as possible. For example, during raiding, they want tanks to be interchangeable for the 5-man level, but they should have a specialty at the 25-man level. Although they envision Death Knights being the best tanks versus casters, they should also play decently well against other foes.