Considering the fact that Titanic was the highest grossing movie of all time and that everyone and their mother saw it between two and six times, I find it odd that there haven't been any references to or even jokes about Titanic on South Park. It's not necessarily a bad thing, since Titanic has been shockingly overexposed in the media(I've seen it twice myself--I'm not criticizing the film), but it would be neat to see Wendy dragging Stan to see Titanic or something along those lines. I may put such a scene in a fanfic, if ever I decide to right one.
Christopher