My son’s friend recently ranted a bit on facebook because he discovered that his employer was checking employees’ facebook pages. I understood his frustration, but I see where he made his mistake.
Nothing you do on a social site is private. Nothing. If it’s posted on your wall, it’s like someone wrote it on the side of your house for anyone passing by to see. If you’ve commented on someone else’s post it’s as though you’ve shouted that comment in the middle of a crowd. Even a private message is only as private as the person receiving it decides to keep it.
If you’re posting something online, just assume that you’ve hired someone to shout it on a street corner. If it’s not something you’d like revealed that way, you might want to reconsider posting it.