It's interesting to consider how the tension in the design choices for HN's discussion board have affected the perceived & actual tenor of the platform:

    1. Votes are not shown, but they affect the rank of posts.
    2. Every post regardless of rank is shown beneath its parent, as in a tree.
    3. Only highly downvoted posts are grayed out or hidden.
    4. The community considers simple agreement to be low value noise.

It doesn't seem like a stretch to guess HN's flavor from a handful of these facts...