https://www.youtube.com/watch?v=ZLJ-5zzbVlE

Speaking of ghosts... will there be eerie burn-in ghosts from a nuclear blast? I don't think I saw any in FO3 or FONV anywhere...

I remember when New Vegas came out, someone said there was a ghost train that came and picked you up, but that was not real =)

My best advice is to ignore the photo posted in the OP (I still don't see anything in that shot), however, you should pay close attention to the trailer at about 1:28. Just behind the power armored soldier on the right.

https://www.youtube.com/watch?v=ZLJ-5zzbVlE

Might be what they are referring to.

Wouldn't be surprised, there was a ghost NPC in Fallout 2.

http://fallout.wikia.com/wiki/Anna_Winslow

Here's what I suspect:

At some point there was an older scene, perhaps showcasing a street and various NPCs and this guy was the placeholder for our character standing there watching. Some time later, they decided to scrap it and do the whole Pre/Post-Great War juxtaposing and re-edited that scene but missed this guy. It was just enough that he appeared for only a brief moment, but he was still there in a scene he was never meant to be in.

In short, just a mistake. No ghost involved.

Seems that is just a glitch, or something like that, nothing serious.