Apparently, from the Neogaf thread, the PS4 version uses a much cleaner and sharper (less blurry) Anti-aliasing method than in the Beta, and better than the XB1 version.
Anyway the fact that DF still didn't publish the face-off must be because it's true. If both versions were perfectly identical they would have said it to the whole world already.
Finally, a limited color stuff should not make the XB1 image blurrier than the full colors PS4 version, it could make it more washed out, but not more blurry. It must be a difference in AA method like many Neogaf people noticed.