Now, it's watch your Ps & Qs for posterity!
As I've said in El Reg posts before, I'd never use social media sites as a matter of course. Being in IT, my use of it is fleeting and then only to understand it.
Between privacy issues (mentioned last week in El Reg), data mining by those who run social media sites, government snooping and linking of contacts and now having anything you say together with your social network--which you may deem undesirable in later life--being recorded for posterity (and undeletable by you), makes social media sites dangerous internet hangouts.
Isn't this clear to everyone?