Going by the clothing worn by the Vaut Tec salesman,the gent with a robotic hand from a screenshot, and the Mysterious Stranger I now believe the Mysterious Strangers from the perk are Androids programmed to protect any one with a Pip Boy.

Flimsy evidence to be sure.Wild [censored] specuation...absolutely.

If anyone else has already proposed this theory then I salute your brilliance.

I'm more inclined to believe that the Mysterious Stranger is human. I mean, they heavily hinted that he has a son in New Vegas, so I'd rather believe that.

i believe the mysterious stranger's a vault tec salesman

You aren't supposed to know! That's why he's "Mysterious"!

I wonder if they've kept the Mysterious Stranger mortal. I always thought it was kind of hilarious in FO1 and FO2 where you could get the perk, and then he could show up in combat, do something stupid, and die. (I once had Ian machine-gun the MS in the back. Oh, Ian. Friendly fire was your hobby.) And then he would never return. Because, you know, dead.

See last spoiler in OP of http://www.gamesas.com/topic/1521576-massive-clue-to-fallout-4-storylinethread