A bug or a possible new WvW feature ?
what ever the orange spot is.. it was behind the camera view in your screen shot…
It was an ele running without armor. Before i could take a second screeshot after i killed him he was disapeared. That´s why only this screenshot, which shows the orange spot on the mini radar.
Regards Seed
As far as I know you get these red spots on your minimap if a player of your server sees an enemy and is near you. Same as in Spvp.