I had to grab the opening teaser and a few minutes in the next act of Medium,
When I looked at what I got, I was surprised at the large vertical shift in the image. The shift is 34 pixels. Because of the way MPEG-2 works, there will always be 8 rows of black pixels at the bottom of a 1080 image. In this case, it is 42 pixels of black. It isn't a result of cropping either. It is a vertical shift.
Here is the WMTV image
and here is the reference image
While looking at the WMTV video, it just didn't look as sharp. It isn't. I cropped a 200x200 area of each image and blew it up to 600x600. Here is the WMTV image
and the reference image
Yes, the reference image has a bitrate of around 35Mbps (MPEG-2).
I haven't done a lot a research into this, but I suspect that in order to fit the HD into the low (IMHO) ATSC bitrate, the video needs to go through some noise reduction, otherwise the complaints about macroblocking would drastically increase. I also do not know what the NBC H.264 video looks like. I never captured it as I wasn't planning on doing a comparison. So, it is possible that NBC has also done some noise reduction.