http://i.imgur.com/Vs3ne6l.jpg
http://i.imgur.com/JJ2q3Iq.jpg
The downgraded pictures were ripped straight from the uncompressed video released today.
If it's not downgraded, then this is obviously Xbox One footage due what appears to be low resolution, lack of AA, and muddy textures. If so, why the hell won't CDProjekt just show PC footage at max settings to REALLY show off the game? I'm at a loss, folks. Does anyone want to contribute? The gameplay footage is undeniably a lot worse than what we were originally shown. I hope CD says something, because the difference is night and day.
PLEASE KEEP IT CIVIL. THIS IS AN IMPORTANT ISSUE.
I don't think personally that the game is being downgraded, not because of trust but more becaue of how game development works and some things I've been noticing with this engine, which might not be finished at all yet.
In your first comparison the swamps dont seem to be the same ones at all, and if they are they have a massive change, not in graphics, but in how they let lightning render them.
Look at the swamps from the 37 minute demo, they are being shown at a day time when the sun shines very nicely with a lot of color, yet they are extremely washed out and grey in comparison to the Downwarren village for example, and when Geralt goes to the harpie's nest, you can see that the grey and blue fog covers all the swamp land below totally changing the looks of the place, this is not regular light-block from the swamps having many trees or being low height lands, this look is intended, and the fog and colors are as well.
Additionally, the shot from the VGX trailer, happens at dusk, according to the color of the sunlight, and to the sky above high which is dark already transitioning into night, this changes the scene dramatically, sun light colours things much more as night is arriving, hence when during noon things that have the sun shinning on them glow white, and when they have the sun shinning on them at dusk they can be orange or even red. This time of the day also darkens shadows a lot, since its close to night, and it creates very strong contrasts.
Finally, I don't know why, but your screenshot from the 37 minute demo is especially washed out and grey, compared to when I look the video in my PC, your versions of the VGX trailer are consistent with how it looks for me though. Here my demo footage looks much closer in contrast and depth to the VGX trailer.
Now the second comparison, the SOD trailer is likely newer footage than the demo, because its easy to capture a trailer with snippets of footage from a modern build, also it has scenes cherry-picked, and it probably is altered to represent release quality more closely, also, its just a different scene. It might also be running at higher graphics settings than the demo, maybe in Ultra as opposed to high, being that its likely newer. Jose already said the game looks better now, than how the 37m demo looks.
One thing I've seen from all footage is that the lightning and whole situation changes how graphics "seem" to be a lot, even in footage supposedly from the same build or released at the same time, this happens in the SOD trailer, VGX trailer, and Debut trailer. Because of this I find it VERY difficult to judge graphics fairly. You could just put a screen of the scene with Yen in the SOD trailer, together with one of the part with Triss using her magic also in the same trailer, and it looks way worse.
Once again, your version of the 37m demo looks way worse than how I can see it in my video player, and here its indeed closer to the SOD trailer
The reality is that whether the graphics are significantly changed or not, its all speculation if its an actual downgrade, especially when you look at footage that is from a moment when optimization hadn't started yet. Demo builds are the ones that look the worse, and they are always several months behind everything else, tweaked to work rather than to showcase graphics, and the engine CDP are working on isn't fully ready. Add to this what has been said already by others, that this is not Ultra, that the game will look better than not only this but also than the trailers, and it just seems likely to me that its definitely possible.
All that's left is to trust or not despite what I said before, and given the context, its extremely logical the demo looks worse than the trailers, now combine that with the studio's previous game released and how it evolved, I think talking of a downgrade like its almost sure is exaggerated.