There is a post floating around Facebook. It comes up in my feed almost as often as Facebook announces updated Privacy settings.
You can find more information on Snopes.com, but this post on www.urbanlegends.com puts it far better than I can.
Friends and family please follow….For the next little bit weeks I will be posting this and please once you have done it please post done, because those of you who do not keep my information from going out to the public I will have to DELETE YOU: I want to stay PRIVATELY connected with you. I post shots of my family that I don’t want strangers to have access to!!! However, with the recent changes in FB, the “public” can now see activities on ANY wall. This happens when our friend hits “like” or “comment” ~ automatically, their friends would see our posts too. Unfortunately, we can not change this setting by ourselves because Facebook has configured it this way. PLEASE place your mouse over my name above (DO NOT CLICK), a window will appear, now move the mouse on “FRIENDS” (also without clicking), then down to “Settings”, click here and a list will appear. REMOVE the CHECK on “LIFE EVENTS” “STATUS UPDATES” “PHOTOS” and “COMMENTS & LIKES”. By doing this, my activity among my friends and family will no longer become public. Now, copy and paste this on your wall. Once I see this posted on your page I will do the same.
In short, update your privacy settings so your posts can only seen by friends, put your friends in Groups/Lists so you can be sure only specific friends can see and act on your posts, and by all means, avoid doing everything in the italicized text above, and tell your friends to please remove it before people stop interacting with their posts entirely.