Just to reiterate what everyone has said, grain in film is natural. JBL, please stop posting nonsense in this thread when you clearly have no understanding of what you're talking about. Films are art and entertainment. It's not so much about looking out a window as an art style. Do you judge paintings because the colors chosen aren't things you normally see with your eyes? No. The same should go for film.
Back on topic, I think the clear winner here is the Bluray version. The noise in the film is actually that, not grain. Technically, the term for what we're seeing here is referred to as gain. Anyone who has worked with prosumer and pro cameras before know that a higher gain setting can help compensate for low light shooting, at the expense of adding extra video noise.
I also recall hearing or reading somewhere that Mann chose to add even more of this noise in post production. I can't attest to whether this is true or not, but if I find the article or remember where I heard it from, I'll post a link.
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