- Diversity of opinion (that's where noise-filtering tools like Flipboard and Zite come in)
- Wired: Sharing Information Corrupts Wisdom of Crowds
- How social influence can undermine the wisdom of crowd effect. PNAS USA May 16 2011 doi: 10.1073/pnas.1008636108
- Investment firm launches Twitter-based hedge fund (hmmm...)
Another way of saying this: the social media echo chamber is a dangerous place, tricking you into thinking things are happening when they're not.