30023s also allow nested replies, which kind 11 doesn't. In terms of semantics, how is a blog post distinct from a post on a forum? A lot of ways! A blog post is published within the context of an author (or publication), a forum thread is posted within the context of a topic or board. Blog posts are the focal point of the comments, a forum topic is a starting point for a longer discussion. Blog post comments may diverge into different sub-topics of the blog post, forum threads are "on topic" (or, "off-topic" as the case may be). They are entirely different media, and don't need to be squashed together.
