I am thinking of trying a blood spec for my arena teams with all dk's. This is what I was thinking to spec them.

http://www.wowhead.com/talent#jcGMfsbruszZbG:0RV0zRM0m

My rotations would be mostly deathstrike heartstrikes and necrotic strikes. Let me know what you guys think. My frost dk's are capped around 1600. If they could heal up some I am sure they can go higher. Blood would allow them to heal as they dps.