As of patch 3.3.5 this article will talk about the best places to go in order to get raid gear for your Death Knight.
Since there is no longer any need to farm older raids like Naxxramas, Obsidian Sanctum, Eye of Eternity, and Ulduar; unless you want the achievements, the focus will then be at the four newest places: Trial of the Crusader, Onyxia, Icecrown Citadel, and Ruby Sanctum.
There will be hefty raiding requirements as far as gearscore is concerned to get into these newer raids and what tends to happen is the gearscore goes up exponentially every time a new raid zone is released even though the difficulty of the older ones hasn’t changed.
For example, PUG’s frequently allowed players with a gearscore of 4200-4500 or more to participate in the 10 Man and 25 Man Trial of the Crusader. Today because of the substantial amount of increases in gear in the 3 newer raid instances, the gearscore requirement is usually above 5000.
Not to worry, there is no need to even go to a raid to get 5000 gearscore now.
Start out by doing Random Heroics to gather Emblems of Triumphs and when possible try to specifically get into Heroic ICC 5 man dungeons everyday. It’s best to manually select them first as there is a chance that after a player becomes locked to the instance that via random queue they can gain access again allowing for faster gear collection.
By the time all of the Emblems of Triumph gear has been purchased and all of the miscellaneous items are gathered from the ICC 5 Man’s, the average player sits between 4900-5100 Gearscore and is ready for raids.