I had an interesting exchange with someone from the BBC at the RTNDA conference I attended last week. I was on a panel devoted to ethics in digital journalism, and much of the discussion and concern among the audience surrounded user-generated content, specifically user comments. Toward the end of the discussion, I made the point that people in the audience who were expressing disdain for the practice of inviting in user commenary should realize that this is about more than just controlling trolls. Wikipedia and Google, I said, were built on user input -- small acts of creation by millions of users. It's the 'collective intelligence' meme that has built powerful, new information tools, fundamentally transformed business and made billions of dollars for some on the Web.