Seeing the trailers for Black Swan reminded me the Korean horror film Wishing Stairs from a few years back. I think it's available on Netflix streaming right now. The movie has a long, atmospheric setup, and, in the tradition of many Asian horror films, gets a little confusing near the end, but it is not too bad for the genre.
The beginning of the trailer below will show you a few of the similarities. (In Wishing Stairs, Giselle is the central ballet.)