When my DD#3 was away at college Facebook was the way to keep up with what she was doing. She also posts pictures all the time on there so it's how I got to see pictures of her.
All 4 of my children are on facebook but only DD#3 is really active. She's at home right now, she graduated with her masters and is getting married in October. I hardly get on there any more. I just check it once a week or so and see what's going on with my friends.