Loved it. A quiet episode, but one that did an excellent character piece about van Gogh.
The monster in general was a weak part of the story, but I liked how they dealt with its death. I also liked seeing those little references to Rory, showing he hasn't been completely forgotten.
The best bit was by far the end. I always wanted them to take someone to the future, and at least van Gogh didn't try to disprove it or anything. He just took it all in, and the speech at the end by Bill Nighy's character was moving and brilliant. Was reminiscent of Father's Day and The Unquiet Dead, but something new as well. One of the best character pieces I have seen in nuWho.