People like to blog about what facebook, twitter, or other social media applications are good for.
They are all wrong. Actually many people have good ideas about how to use social media, but it is typically from there own perspective. Don't take anyone's word for the purpose behind it and how to use it. Jump in any find your own purpose.
I use facebook and twitter to tune into ideas from many other individuals around the world as well as to promote sharing of ideas between various cultures and groups. It is past time that we move beyond tribalism and treat everyone on the planet as members of our own group. Being in touch with many people from various backgrounds is the best way to overcome our cultural biases.
Very seldom do I refuse a facebook request to become friends. Learning to share ideas and get along with everyone supersedes any fear of being exploited.
As well as the many friends I have met online, and never will meet in person, there is also many people who I first met online and later met in person. For me social media is not about keeping track of my friends and relatives, but is about interacting with many people around the world as well as making new friends.