I like these things, and I've added myself, but... there've been similar ones in the past, they don't stay up to date. I feel like without some way for users to know, six months from now, that the information they're looking at is still accurate, any given iteration is never going to be very useful for long.
An idea that's floating around in my head, I think I've mentioned it before, is that a service like this could require everyone to occasionally confirm that they're still in the same place. Send out an email once a month, they can click a link or reply to remain on the map, or ignore it to be removed.
I would expect that people move so rarely that the information would remain mostly up to date for years or even decades. Am I wrong?
I can also add a comment somewhere telling people to notify me if they tried to reach someone and failed. In that case I would try to contact the person to see what's up and, failing that, remove the marker myself.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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