The actors have improved so much over the years. It's nice to see such a good change.
As for the movie itself, the minor changes made didn't deter from the story too much. You really got a good idea of just how serious this movie is when Hermione Obliviates her parents and all their pictures of her disappear. So profound, so moving.
I'm so glad they decided to divide this book into two movies. It really allowed them to focus on the details, which is awesome.