[xibernetik]

My family uses Facebook heavily to stay in contact since we tend to be in different countries, along with Skype and email. They moved to this long after the initial craze because Facebook offered some really compelling advantages.

For my tech-savvy parents and non-tech-savvy grandparents, it provides an easy way to share/view photos. Using email/IM means having to come up with some sort of filing system for photos, whereas Facebook just provides it, along with captions which can be useful for travel albums.

It's a broadcast system with less urgency than email. If there's some photos or a story from daily life you want to share, emails like that will get lost in an overload of tasks and requests. IMs are easy to ignore and hard to dig up. Facebook provides a way to find out that hey, something interesting happened, and when I get around to it I can browse what's up with people I care about.