Every new technology brings with it the capacity to screw things up in an entirely new way. With social media, it's now become possible to turn what was once a verbal gaffe behind closed doors into a public peccadillo.
Social media mistakes - a tweet published accidentally, an ungracious response to a Facebook wall post - are bad enough in a personal context, although they can usually be straightened out. But when such things happen with a corporate Twitter account or some other branded outlet, they can be messier by orders of magnitude.
It's not just that the wrong message gets out to that many more people, or that said message is associated with a multimillion-dollar name, or that it might well be enshrined forever in some digital archive you can't erase. It's that, on top of all those things, a mistake speaks volumes about your (in)ability to manage social media effectively.
It's best to think of such accidents as a "when," not an "if," situation.
