Facebook is excellent for keeping up with friends, and can be a big help in emergencies. A very close friend of mine was recently niftar in Cleveland, and he was buried here (Israel). Facebook was a huge help in sending out tehillim requests, as well as keeping everyone informed about when the plane was landing and the time to meet at the cemetery.
My kids have Facebook, as it helps them stay in touch with their friends from America. I have rules about their access that I enforce. I have their login names and passwords, and I log on as them when ever I want; that way I can check on their friend lists, see what they are doing, etc. They are not thrilled about this, but they know that is the rule for having Facebook. It’s better that they know that I can and do go online and check. (BTW, they have limited computer time; I passworded their computer, and only I know the passwords. Each kid has a certain amount of time per week on the PC, not including time needed for school work.)
Shabbat shalom to all.