There Will Be Blood is a shoo-in for me. One of the most astonishing aspects of the film, to me, went unmentioned by Devon and Amy, and that is the truly historical, almost alien feel of the whole picture. I feel like PTA set out to steep the set in a time and place - and a way of talking and being - that is incredibly foreign to us today, only a hundred years later. That does make this a scary and difficult to approach movie - there's little to experience, emotionally, in this film. But I think in this case that wasn't PTA's goal, and I think that works.
Also, the opening sequence with no dialogue is as stunning and effective as the D-Day invasion in Saving Private Ryan.