It would be nice to see where players are gathered on a map. On Wrothgar for exemple, it would be nice to see which of the world bosses have people waiting to do it. On Imperial City Sewers, it would be nice to see where players from our alliance are at so we can try to join them, even if you are not on their group. On Cyrodill by allowing us to see players on the map we can have an idea of how many people from our alliance are attacking a keep, where they are heading at, etc. Of course, make it completely optional since the map would be crowded by player icons.