After several attempt to make their application validated by the AppStore, South Park editor and developers release the made the story public.

Their application allows iPhone owners to play episodes from the serie. It was rejected by the AppStore as some scene might be "shocking". IF Apple did not definitely close the door to South Park application, it demonstrates one more time how confuse and weird the process of validation can be for the AppStore. Indeed, the same "shocking" episodes are available without restrictions from the iTunes Store.
If we want to go beyond the scene, one can imagine that apple does not want to share revenues, and prefer to have customers to purchase South Park Episodes from the iTS than purchasing an iPhone application from the AppStore allowing them to watch the same episodes from South Park servers (potentially for free).