Business Insider says that the usually calm and collected Facebook CEO Mark Zuckerberg “seemed to melt on stage,” while answering questions from industry insiders at the All Things D Conference. They also report that Mr. Zuckerberg told the crowd that he doesn’t believe in giving users the choice to “opt-in” to privacy changes because back when Facebook introduced the “news feed” everyone freaked out — but it turned out OK in the end. [More]