I’ve looked at this video several times and I’m convinced:
This shape is more squat and the proportions finally seem correct to my eyes.
We’ll all know for sure in six weeks or so when Apple holds their event.
Update, Monday September 3, 2012: Minutes after posting, I learned this video ripped off images from another site. See those images and others in this post at 9 to 5 Mac, with proper credit given: New physical mockups give a look at the upcoming iPad mini’s possible design