Update: We're still looking at if this is possible - we haven't forgotten about you :)
There's only a limited amount of information that we can pull from the Netflix API, we're looking into if indeed it's possible. Awesome idea though.
Unfortunately, not at the moment.
Found this link, if that can help : http://movies.netflix.com/Subtitles.
This would be a killer feature, in my opinion would be the best feature to implement. Because that's the biggest problem is a lot of movies have subtitles you can't remove, it would be amazing to know before hand instead of finding out the hard way.
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