Darren Aronofsky has made a few films where the characters develop similarly... pi, requiem for a dream the fountain, all of those had a bit of a downwards spiral into madness. with his usual formalistic approach the director delivers quite a treat, visually speaking, he returns to his expressionistic style after his endeavor with realism in The Wrestler. Black Swan dramatizes the realm of dancing significantly until the barrier between reality and fantasy seems almost nonexistent. the casting is great, Natalie Portman is amazing indeed, Mila Kunis pretty much plays herself again....the score is nothing short of what we would expect from Clint Mansell.
the films did have its flaws, but all in all the film gets increasingly satisfying as we move towards the ending which seems spot on. this is a solid piece of art to say the least..