We already know that the game runs at 60 frames per second in 1080p on PS4, 60 frames in 720p on Xbox One. So on paper the PS4 should perform better. Take a look at the trailer below and make up your own opinion.
As you can see the PS4 is currently out performing the Xbox One in many ways. Even down to the sky. You may notice that the Xbox version is full of clouds and the PS4 is not. Well Kojima tweeted regarding that;
"In addition, in the PS4 version only the daytime sky is not a static picture. It includes special processing based on atmospheric simulation."
Also, the guys over at DualShockers have created some gifs of still frames from the trailer. The best gif for showing the major difference between the versions is the one below. It contains a lot of difference textures plus the text on the sign is a lot more sharp on the PS4. Personally, I think the Xbox One version looks like a game from the last Generation (PS3/X360) but I will let you make your own mind up
More gifs over at DualShockers