This is interesting new (to me) software: Geni.
It's a cross of genealogical record keeping and social networking. It can be edited by the people you invite. They can add pictures, details, information about their in-laws, perhaps, and much more. I'm hoping that together my sibs and I can figure out whom we're actually related to and how. Heck, I'll settle for who's still alive and the first names of all my cousins. We'll see how we do!