James Cameron, amongst other headline proponents of 3D, laud the format for giving a feeling of "looking out the window." Part of this is forsaking one of the oldest cinematography tricks in the book - depth of field. Directors and directors of photography commonly use shallow depth of field, that means having things at a specific distance in focus while the rest is out of focus, to highlight an actor or object that they wish you to pay attention to. This cannot be done if you want to achieve the window effect because things in the distance are required to be in focus along with the things that truly require our attention. Up to now there really hasn't been a movie that allows you to analyze the artistic decision between an infinite or shallow depth of field because it's a decision that is made as the camera is filming. Tangled has been rendered differently in 2D and 3D so that the 2D version looks and feels more like a traditional film while the 3D version is able to take advantage of its format. This is the first time that I've been depressed to not have a 3D TV on hand.
Note: It can be difficult to tell the difference at this resolution, so click on the pictures to see the difference at 1920x1080(1080p)
Disclosure: I saw this movie twice in theaters in 3D, once in November and once in December. I've watched it at home
twice three times many times in 2D 1080p via Blu-ray.