Yes, that's well known thing. It's called the "soap opera effect":
http://en.wikipedia.org/wiki/Motion_interpolation
http://forums.cnet.com/7723-13973_102-402081.html tells what to do about it: turn off Automotion Plus or such picture optimisations.
Kees
Why is the picture so clear on movies, it looks like soap opera filming and cheesy, does anyone know how to set it up so movies look like film and not video?

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