According to The Film Stage:
Cronenberg's 'Maps to the Stars' is rated R for strong disturbing violence & sexual content, graphic nudity, language & some drug material.*raiseseyebrows*
— The Film Stage (@TheFilmStage) January 8, 2014
Australia hasn't given the film a classification as yet, but my recollection is that Cosmopolis was rated "R" in the US, but it was MA15+ in Oz. I'll keep you updated if and when we get details about Australian classification or release.