World of Warcraft: Wrath of the Lich King: DK: How to DPS

Death Knights are the newest addition to the World of Warcraft, and they are a class that seems to do well doing damage in any of their 3 spec trees, however there are obvious advantages to all of the trees, and I will do my best to explain the best ways to do damage in all 3 trees that apply to nearly all situations.

Blood
Blood is a nice spec for both staying alive and dishing out some damage. With moves like heart strike and pestilence, doing damage to multiple targets becomes quite easy. Blood is a decent spec for solo grinding, because you'll be able to take quite a few mobs at once without too much of a worry of being killed, because you're going to be able to heal yourself quite well. Blood is all about staying alive, and regaining health while in combat. Your crit rate and expertise will be higher in blood as well.

Frost
This has been my favorite spec since I have started my death knight, and I will probably continue in this spec even after the patch which will come out soon. Frost is based mainly off of crits, because your frost abilities have a chance to crit about once per 10 seconds while in combat, if not more often. You're also going to be able to do significant damage to multiple targets through the use of diseases and howling blast. If you wait until all of your targets are infected with frost fever, and then waiting until your crit is good, then throwing out howling blast, you're going to hit all of the targets near you for over 2000 damage in most cases. Frost also makes excellent tanks in instances, but the damage is awesome for solo grinding, even. The only down side to this higher dps is that you will have slightly increased downtime between frost and blood.

Unholy
Unholy rely both on their diseases and their pets to do their damage. Of course they're going to hit nearly as hard with melee attacks, but a large portion of their damage comes from plague strike and icy touch, and then pestilence spreading these diseases across all targets. Also, death and decay is more of an unholy ability, which even further increases your damage against larger mobs. Your pet will do decent damage, and when specced and glyphed properly, he will have nearly as much and even sometimes more hp than yourself, making him a decent off-tank in ermergencies.

Overall, all of the specs for the Death Knight class are good for doing damage and leveling right now. After the patch comes out, I seriously doubt that this will change. There are minor changes to each tree, but each of the three specs will still do excellent damage per second.