Hover your mouse over your friend's name on the right, and it will tell you where they are. What would be handy if this would also show you a dot on the map, just for THAT friend - that way you're not overwhelmed with moving dots on the map.
That would be a good solution, Zany! Or perhaps the map would only show up to <number> of selected friends (would require some sort of modification of the friends list to specify friend selection), or only the <number> of friends closest to your current street, or something like that.
I like the idea of hovering over a friend's name to find their dot on the map.
However, I'd like that to work only for mutual friends. I do not want someone to be able to make me a friend, and then stalk me in-game even if I don't reciprocate.