Looks cool. Suggestion: Require people to request discussions from others to sign up/comment/participate. You could gain big traction by getting big names to do conversations and likely monetize by having sponsored conversations.

Major thing to avoid would be what happened to Quora where all the comments were gamed by people trying to resume pad.

"Thank you for your question, the history of privacy goes back millennia to Cleopatra's Royal guards... In summary, duckduckgo is a search engine focused on privacy"