Thanks for pointing this out. I think there is a possibility for both preserved, text-based comments to exist alongside live, audio-based discussions.

I wouldn't want the HN experience being degraded by not being able to access relevant discussions about posts in the future, but I think those who are deeply interested could benefit from the ability to speak live about posts with others (including the OP) in a more intimate and fast-paced setting.

The roundtable for this post is a great example. There have been some super valuable comments in this thread as well as great discussions held in the audio chat room (except for the rick-roll, that is!).