You can't beat a blood spec for survivability. My character's name is Necrotíc. I generally use the blood spec on my armory for raid tanking and progression stuff or a dps based unholy build for ripping through 5 mans.

I have a separate rotation on each build depending on whether I am single or multi target tanking. I have gotten these straight from the elitist jerks forum and found them to be pretty spot on for multiboxing.

Cheers