People tend to think of ignorance in terms of something absent, as a gap or a hole in conceptual space. That's a pretty ignorant view of ignorance.
Ignorance, by its nature, is represented in peoples brains by neural patterns, is exchanged in communication, and is clearly evident when mob-think pervades Facebook discussions. Urban myths are ignorance encapsulated as the stories of our modern apocrypha.
Ignorance, when realized consciously, can be variably hope, fear, or some other longing, but never faith, confidence, or trust. Without knowing what others don't know, ignorance is not just bliss: it pervades everything you say and do rather deeply and very materially.
Fighting ignorance with ignorance is not like fighting fire with fire. It is more like burning your neighbor's house down because you see fire on the horizon. That strategy is not very likely to be successful, even if it you are taking action.
This is the truest danger of social networking: ignorance is a learned meme.