I still haven't seen ZD30, but Michael Moore's assessment sounds pretty reasonable to me. He argued that the movie is, in fact, an anti-torture movie:
"In the final third of Zero Dark Thirty, the agents switch from torture to detective work -- and guess what happens? We find bin Laden! Eight years of torture -- no bin Laden. Two years of detective work -- boom! Bin Laden!"
Personally, I've always thought the brutal portrayal of torture in the movie (so I'm told) is the greatest argument against it, not unlike the release of the Abu Ghraib photographs.