Two indicators exist, red meaning the highlighted player is an enemy and green meaning he is a teammate. In certain gamemodes such as Rambo, players who don't have the bow are neither, they're neutral. When they are highlighted, they are marked as an opponent.
Technically, this feature isn't very necessary, but it would be nice as it is a correction in identifying certain targets.
For it as a feature, when a player is neutral, he'll be highlighted yellow as it is the color meaning it.
Comments, thoughts, ideas, or suggestions?