It's a good deal more dissonant than Bruckner, but I understand the comparison - say, with his 9th. For me the parallel is more with Mahler, especially symphonies 9 and 10. And some of the climaxes definitely rank with the Gothic...
It's going to take a lot of listening to in order to get my head round the piece, but I have a feeling it's going to be my discovery of 2011...