The thought did occur to me that they were similar, and maybe ghosts were the Traveler's second attempt after the Vex were corrupted. But the ghosts were made as one of the Traveler's true final acts, so I don't think they would be the Vex themselves. That wouldn't make sense for the Vex's part in the Collapse, before the Ghosts were made. Not to mention the fact that we know the Vex are living organisms in the white fluid in the stomach area. The rest is a battle-suit. The one big eye thing is a bit of a similar design though, so I won't be surprised if it turns out they're related somehow. = ) It would be cool, if we get to defeat the Vex in like Year 9, if our ghosts could inhabit their frames and use them to battle beside us. Or maybe just for a mission at one point, something like that. = P