Yes this happened with the 1.09 update, in this update the "Hitman" gained the ability to spawn in random vehicles(random in color & type). I posted this on the first day of 1.09, when he killed me in a red landstalker and a white patriot. It happens when there is already a vehicle in the place he is going to spawn, if there is one there, then he becomes the driver, if a vehicle is not already there, then he will spawn in his trademark Sentinel XS.
He resembles Agent Smith from the Matrix.
Imagine if there was a high tech elite NPC performing like that. A devious hitman that can take immense damage and can shapeshift which he then proceeds to follow you around the map while also being able to make clones of himself. Mike Toreno deserves this role!
Awesome, never even thought of it that way, lol. I will from here on out refer to the "hitman" as "Agent Smith", lol
P.S. I was wrong, it happened in 1.08;
"...-The "Assassin" in the black sentinel XS CAN now appear in any random vehicle(he appears in whatever vehicles is closest to his spawn location)...."