After watching all of the comparison videos and crawling through all of the screen grabs I can get my hands on, I'm going to have to conclude that Digital Foundry dropped the ball on this one in a big way. No one else is showing the kind of gamma level differences that they're showing. No one. So, unless everyone else is actually throwing around the same video content just edited differently, Digital Foundry are recording deeper blacks than the everyone else and their independent recordings. This puts them as the odd man out. The deeper blacks in the Xbone versions of their content provide a favourable detail environment; the human eye simply perceives more detail in a darker image than in a brighter image, even if there really isn't. They also don't have any Xbone multiplayer footage, and considering it looks... not good, it raises an eyebrow for me. I won't make claims about shilling, but I would suggest they take a more accurate approach next time. Crushed blacks give the illusion of a more detailed image, whereas the PS4 and PC versions provide a more "realistic" IQ in terms of lighting, shadows and overall shading. For a major tech group, it's a pretty big fucking misstep.
Every one else's content, though, displays the PS4 and PC version clearly ahead of the Xbone version, with the aliasing obliterating the IQ of the Xbone version. It's hard to appreciate the finer details when it simply presents as a last gen game to me. The crispness of the PS4 version makes a much larger difference than I would have actually thought, and I'm one of the people trumpeting the difference! The diminished aliasing on PS4 just says "next gen", where as the jaggies on the Xbone make me think it was an Xbox 360 game, even though the model detail and effects are simply not possible on that hardware. It's probably psychological conditioning after seven years with the 360, but it's worth noting. If you told me the Xbone version was the Xbox 360 version with a straight face, I'd probably believe you.
With the Xbone struggling to keep up this early in the game, and titles like Shadowfall advertising what a pure PS4 title is capable of, there cannot be any doubt left that the Xbone is simply out matched in a big, big way.
It's going to be a long ten years at Redmond...