Oversharing can come back to bite you - http://venturebeat.com/2010/04/23/blippy-credit-card-citibank/

Social Media ROI?  How about Return on Ignorance - http://www.twazzup.com/?q=ROI+%3D+return+on+ignorance&l=all

And we need to watch each other's backs on social platforms.  Because opt-in by default is something we all need to be aware of -http://gigaom.com/2010/04/22/your-moms-guide-to-those-facebook-changes-and-how-to-block-them/