There MIGHT be a slight chance that he MIGHT make some sort of cameo in Halo 4, but right now, the main focus of Halo 4 seems to be about the forerunners. We will just have to wait and see what happens.
While yes, that does indeed look like the Arbiter, I really don't understand how "photo of half of maybe the Arbiter in the screenshot in the Halo: Anniversary level selection menu for The Silent Cartographer" = "Arbiter will make an appearance in Halo 4".
This is not to say he definitely wont, just that I fail to understand how one leads to another. I've seen this kind of "logic" for years from people speculating about games in development, and all it does is lead to ridiculous rumors and mis-information.