Tim Hecker -
Ravedeath 1972 (2011)
This artist has been getting a lot of plays from me this year, this album in particular, but his older stuff is just as good. It's not quite dark ambient, but it does a great job at straddling the line between background and foreground noise. It's something you can actively listen to, but not have it get in the way of whatever it is you're doing (for example I listened to this while working on a 45-page paper last semester). The sound can best be described as desolate, the soundtrack you'd expect to be playing while walking through a ruined post-apocalypse city or something. Definitely worth checking out if you're looking for something from this year.