interstellar wasn't a great film, but it's one of zimmer's best recent scores for sure. really, really good stuff. the first sherlock holmes movie (the RDJ one) is some great stuff too. I'm not a massive fan of zimmer but when he really goes for it he can still knock it out of the park. (to be fair, i also think that Grand Budapest Hotel's soundtrack is wonderful)
sadly--and i dunno if this has any bearing on its life on the award circuit, probably not--the interstellar soundtrack release was completely botched. brutally trimmed down to fit CD length, mastered nothing like the music that actually appeared in the film, and missing some of the most memorable cues. in fact, the organ motif that everyone remembers from the docking sequence was not even included originally; after a bunch of fan outcry, it was finally added as a bonus track for anyone who bought it digitally, along with a couple of other tracks for the (sadly still quite lacking) vinyl release.
funnily enough, the best version of the score was only available on the studio's "for your consideration" website. there were just a bunch of MP3s sitting there you could download individually that included far more of the actual score than the retail releases. not sure if that's still out there, but if you're interested you should poke around and see if it's available still.
kind of funny and frustrating how such an influential (there are movie scores that are STILL ripping interstellar off wholesale--which is funny considering a lot of interstellar is borrowing from philip glass but never mind all that) score is actually really difficult to listen to properly.