Originally Posted by
Tarazet
From what I've experienced, Unholy is not just the better spec, but it's also by far the easier one to play in a raid environment. Watching for procs constantly takes your concentration off of what's going on. If you can raid well as a Frost DK, you can play anything. Unholy is a finesse spec which has you planning the entire fight starting from the beginning, but the priority by which you use your abilities is more predictable. Nothing ever really happens to upset your rotation.
With the abilities your ghoul gets while transformed, you can provide better utility as well (extra stun and interrupt).