I have it in Natural / eco bulb (since this was the setting zombie said had pretty good color out of the box).
It isn't the movie as I can see the banding on a white/grey screen too. I've only tried it with my HTPC so far, connected through my Pioneer SC-07.
I haven't received my mount yet so the projector is right-side up, about 13 feet back, on a bookshelf. Once I have the mount installed I'll see if it changes.
edit to add: I see it on both HTPC and Xbox360 so I started experimenting. Since I have it temporarily on a bookshelf I'm using almost the maximum amount of lens shift horizontally and quite a bit vertically, to move the image down and left. Most of the banding is around the center-left; I can't see any at all on the extreme left and right side. Maybe it's just an artifact of a lot of lens shift?
I also think THX looks a bit better, Natural is a bit overblown and is very noticable in a web browser. THX looks more 'accurate'.
Here's an image showing it, taken from fairly close up since my cell phone has a pretty lousy camera, with an added rectangle to highlight the banding region. You can see it from seating position and it's definitely noticable in bright scenes with panning. It's a very subtle effect but it's there.
Edited by garrettmoore - 11/17/13 at 12:46pm