Well, today I received my 970. As you know, I also have the 971.
My display is a year-and-a-half old Sony 57" CRT RPTV (KP-57WS520) which has been fully calibrated, tweaked, and ISF'd. 1080i native.
My comments are not yet definitive and I'll post more later this weekend; I need to do more A/B comparing, but I spent well over an hour tonight with some film-based DVDs which I'm very familiar with.
The results may surprise some.
After re-calibrating for each player, I am leaning toward the 971. One of the main reasons is the vertical squeezing at 1080i on the 970. I find it unacceptable. Period. It's just too distracting for me. I also think this is one reason why the image is very slightly sharper than the 971. I think if this image was not compressed, it wouldn't look as quite as sharp as it would be spread out more. I say that because at 480p where there is no compression, the image is not quite as sharp. Still good definition, just not quite as much if you know what I mean.
In addition, the 971 is a bit cleaner - that is, fewer artifacts.
Finally, if you factor in the Faroudja deinterlacing, that adds more impact.
As I mentioned, I'll be doing more comparisons and post more thoughts later. By the way, the 970 makes a very good 480p component player.