If trailers start cannibalizing bits and pieces of a score, then you'll probably know that it has something that appeals. So far, I've counted 2 which had used a few bars off this track, and that's The Mist and I Am Legend. I'd bet there would be more to come, soon enough.
The clip above is fan-made, splicing together visuals from the movie and laid out against "Death is the Road to Awe" from the soundtrack. You can go ahead and watch some of the stunning visuals, unless you do not want to be spoilt in any way, but bear in mind you'll probably won't be able to figure out much of the narrative since it's re-edited for this almost 9 minute track.
What works too, is if you close your eyes and listen to the score itself. I'd like to think that the movie will not be as powerful if it wasn't for Clint Mansell's score. Portions I dig - 3:10-4:44 (including those bits of the dialogue that fit so nicely), 5:02-6:28, 6:40-7:30. Wah, want to tear already.
I would have gotten the DVD of the movie if it included a lot more extras, but currently for those who have bought it, head on down to Darren Aronofsky's site to download the commentary piece he did, which of course for some corporate reason, was not included in the DVD itself. I'm holding back for a more proper release, probably by then, in the next generation DVD format. You can read my review of the movie here.