This film wasn't exactly what I expected, having only heard people talk of it, while avoiding everything written about it. It was tense, and off-putting, but somehow still interesting. Tonally, it had some trouble when it came to the question of whether to make this "The Wrestler" for ballet, or simply to make "Requiem for a Queen".
The director decided to go somewhere in between, and there-in lies the off-putting part. I give films more of a chance than the rest of the audience, but I can sense which parts of a movie are going to get to other people more than will affect me. This one will sit with you for a while in the pit of your stomach, but I'd personally be interested in seeing it again. Even thinking about it makes me uneasy, and that's hard to create with film alone. There are some pretty disturbing scenes, which will likely be unexpected for an audience who doesn't know the director by name (though he did not write the film, he shaped it from other screenplays and ideas).
There is something within Black Swan that makes it an obvious cult film, one that you'll be unable to watch just once. Liking this film doesn't preclude how much you loathe the idea of ballet. Natalie Portman does a phenomenal job, and is very anti what you've come to expect from her. Subtly, she reaches a new stage in her career. Please god don't let her turn back now.