Don't by-sa Photos with People in Them
Copyright Virgins
Crap! Now I have to go back through my Flickr photos and mark all those that have people in them to by-nc-sa instead of by-sa. Copyright law is a pain.
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I believe this only applies for photos in which the people are recognizable. That is, if you take a photo of a crowd, and you can't identify any of the individuals, you're not obligated to get a model release form from any of them.
But, yeah, by-nc-sa would be the better way to go.