I dug this, good point, these can be a great way to keep in touch with family and even find old friends. I have found quite a few old high school friends, and even made freinds through online games that have eventually wound up on my myspace lists, and met in Real life to become true friends, not just cyber-buddies.
You do also bring up that this information you post becomes public, even with certain settings, you are posting your inermost feelings sometimes, and silliness of yourself at others.
Now the biggest point though is the time... Time can get spent so quickly and go by so fast when you get deeply involved in the social networking sites, as with other internet functions such MMORPG type games i.e. World of Warcraft, Lineage II, Anarchy Online...
It can become an obbsession for some. And for some of us, just one more thing to budget our time too. I say budget wisely.

You've got to love these feminists who are so independent they refuse to take their husbands' last names, except when it's convenient. Instead, in their "independence" they continue to use their fathers' last names. Go figure.

My brothers and sisters are scattered throughout the world because of jobs and military committments etc etc and we just email each other as a group. Nothing fancy, just plain simple email.

Phantom Panther--What's the difference between a man keeping his father's last name and a woman keeping her father's last name? Now you can go figure.