Given that Tim Burton is directing it, I hope that they don't try to shoehorn it into a PG rating, and give the editors the latitude to make it, firmly, a PG-13 film.
The Disney animated classic is still the best rendition of the story for children. It's excellent, IMHO, and I don't see as much of a need to do that again, as I see the need for a great, live-action rendition for adults.