Anything online starts with the assumption that it wants people to talk, chat, collaborate, share, or so on. From there, almost everything figures out how they want people to do one of the above, then figures out how to organize in. In Yoomoot's case however, organization is step two, not step three, or in other words, it's co-equal with the question of how people should organize. This leads to a format that is bulky enough in the short-term that most people would ignore, but pays rich dividends in long form discussions.