I've watched the first two movies (UK versions, but identical to the US encodes) and I definitely believe some filtering took place...especially on the first movie. However, as much as I don't like filtering, it doesn't look that bad as the image doesn't have a waxy or unnatural look to it. However, there is hardly any grain in it and the image really lacks finer detail (though it's true it could simply be due to the source material as this seems to be a softer looking movie). With all of that being said, I would still recommend these if you enjoy the them.
(I'm viewing in a dark room 8 feet back from a 60" ISF'd SXRD A3000 at 1080p/24 using an Oppo BDP-83.)