It has to be PG. I cant see it being PG-13.... Sure the movie is dark, but so was ESB... I know it is supposed to be darker. But all the merchandise is directed towards children (M&M's, Hasbro [the figure packaging are more youth oriented, which I love though]) I still stick with the PG rating. In May, if I am wrong, you all can rub it in my face...
I can see it getting a PG rating in Canada. One up from that is 14A. That would look funny beside a Star Wars film.