I thought the movie was beautiful and brilliant; the music was equally so.
I know this movie is not for everyone; Aronofsky usually divides, like a lot of art. As for not knowing what the filmmaker was trying to tell you, I felt like I was supposed to interpret for myself, rather than for the filmmaker. Instead of saying "I think Aronofsky was trying to say...", I go "To me, this meant...".
Also, I refuse to admit that Hugh Jackman is ever an astronaut in one of his reincarnations. It ruins the whole metaphysical awe of the whole thing. I thought it was a representation of his spiritual journey.
But anyway, the music. It reminded me of some modern Post-Rock, and the way it flowed throughout the movie was interesting. I was looking for ways to represent the musical/choral parts of Sakuntala and the Ring of Recollection in my IB Theatre class, and the way the omnipresent music created an ethereal mood now fits perfectly in my mind.