The problem with Facebook's groups of friends is that the UI hides the functionality. I doubt that one in 1,000 users would have stumbled upon the right process for making a photo available to just a subset of their friends. I've suggested that a better approach to this type of control is to assign "privacy tags" to both people and published objects. A "friend" could then see just those objects of mine for which both they and the object share the same privacy tag.

It would save some of us the trouble of putting similar material together if you could post the presentation somewhere.

This is not much different to observations Sherry Turkle reported in her 1984 book The Second Self: Computers and the Human Spirit. Way back then she noted that young children had trouble deciding whether even simple electronic toys were alive. She proposed that when a toy could be taken apart to see the physical mechanism, children recognise it as merely an artefact. But when the behaviour is controlled via some computer chip, they are more likely to attribute it with "life".