This movie was really well-done and it was so refreshing to get a "realistic" movie about the subject instead of the typical overdramatic action-y movie that Hollywood usually puts out, which really helped sell the verisimillitude.
It was really eye-opening to see typically glammed-up actors look completely normal - Paltrow and Winslet especially, but Damon too, who looked really scruffy in the movie. Everyone did a great acting job too.
Next to the "realistic" style, the one other thing I loved most about the movie was the minimalistic, electronica-style soundtrack. IMO it enhanced the mood more than an orchestral soundtrack would have. It was also really refreshing to get a relatively slow-paced, slower-edited movie for a change. Somehow that added to the intensity.
Just about the only thing I found odd was the ending, which felt anticlimactic and didn't really provide resolution for Marion Cotillard's character either.
Without trying to spoil anything, I found two characters' deaths completely unexpected. Even though the trailers show Paltrow's character dying it still totally caught me off guard, and the other one, well it was more like a "nooooo, I can't believe it, I refuse to believe it!" And the scene with Paltrow's corpse was totally freaky. I mean, it was ultra-freaky. It seriously creeped me out. Anyone who's seen the movie knows what I'm talking about, it's the kind of thing you totally don't see coming, especially when the actor is an A-lister. Usually those kinds of scenes are given to either B-list, C-list, or D-list actors, not someone like Paltrow.
Marion Cotillard was totally hot in this movie too. I'm not sure what it is about her, must be those eyes.
Oh and I hope this movie ends up being a wake-up call for all of the guys who don't wash their hands after touching their junk after using the men's room!