What may give us pause is a couple threat issues. For Unholy tanks, not only are we losing Unholy Blight as an AE threat tool, but Desecration is being split into two talents with the AE slow being a 2-point talent and the damage increaser a 5 point talent called Desolation. While you can probably spare the talents for Desecration, chances are you may have to give up Desolation, and you certainly won't ever get the old-style Unholy Blight back. All this means is that Unholy tanks may want to watch their threat levels for a bit until they can get comfortable doing without a few key threat-causing talents.
Likewise, Frost dual wield tanks looking to take Threat of Thassarian to solve any threat issues from using two one-handers, be warned: The talent does not affect Rune Strike, so it looks like you'll have some feeling out to do too if you want to make sure your threat issues are gone.
Dual Wielding is taking center stage in Patch 3.2. Dual wielders, expect to go Frost and focus on churning out Obliterates with slow, high damage one--handers to take advantage of Threat of Thassarian. Generally, you should probably expect to be going something similar to this 3/15/17 build, picking up threat reduction and critical strike chance from Blood and getting Necrosis and a bit of Blood Caked Blade in Unholy. You'll also want to consider grabbing the Glyph of Disease in order to free up runes you'd use for Icy Touch and Plague Strike for another Obliterate instead.
Unholy Knights will also have to deal with the changes outlined above in the tank section. Luckily, now that the great Blood Strike experiment is over (Blood Strike is back down to its Patch 3.1 level as of this writing, according to MMO Champion), you shouldn't have to drop Reaping. In fact, your rotation will remain about the same. Since Desolation lasts 20 seconds, it should only be wearing off just as you need to use Blood Strike to convert a blood rune into a death rune. The Unholy Blight change means your AE DPS will shrivel considerably, but by all indications, the single-target Unholy Blight still measures up very well.
For raid level Unholy Death Knights, Scourge Strike may still fall short of Obliterate as gear levels go up, but to be honest, I expect that will change by Patch 3.3 if it comes to pass. For now though, you may find Obliterate surpasses Scourge Strike once you're decked out in enough armor penetration gear.
Blood Knights should be sitting pretty, especially since Dancing Rune Weapon is now more powerful and simpler to use. Shine on, you crazy diamonds.
The biggest change to PvP is probably with Frost Death Knights. With Frost Strike losing the ability to bypass dodges and parries and Sigil of the Vengeful Heart getting the nerf bat, Frost burst damage should be significantly lower. On the plus side, Lichborne's cooldown will be 2 minutes, so it's rather like having a free extra trinket or racial cooldown. Unholy Death Knights will have to scrounge up a few extra points for the new Desecration, or just skip Desolation and use 3 talent points elsewhere.
For casual Death Knights, this patch is a treasure trove of gear. You'll be able to find upgrades for just about every slot if you can get a good group together for the Crusader's Coliseum. Check out our DPS gear preview and our tank gear preview for more information.