about the SL blogosphere, pundits, and forums:
repeated exposure to one persons viewpoint can have almost as much influence as exposure to shared opinions from multiple people
From ScienceDaily: People Often Think An Opinion Heard Repeatedly From The Same Person Is Actually A Popular Opinion, via Kottke.
Arab proverb: “If it is said often enough, even the donkey believes it”
Your post made me think of another famous study about Obedience:
http://en.wikipedia.org/wiki/Milgram_experiment