Comment 6 for bug 1409696

Space is at a premium in the status bar, for reasons of both real estate (there just isn't that much room) and elegance (the more icons, the more distracting).

So it would not be ideal to add an extra icon for headsets. Nor would it be practical to change the existing icon to show a headset: most of the space of the icon is taken up by the volume waves, so there would be little room to show a recognizable headset.

However, the actual problem -- "no visual indication that a wired headset has been connected to the phone" -- can be solved in another way. As I have already specified, but has not been implemented yet, when you connect (or disconnect) a headset you should get the same kind of notification as if you changed the volume. And that notification should name, and use the icon of, the current sound output.