You could generalize this to "Become reddit (i.e. anyone can make a new subreddit/discussion-section), and allow mods to set karma levels for joining/voting/commenting/submitting on a per-subreddit basis".
I'd hesitate to go quite that far, as that seems more likely to splinter the community than anything else.
Today's post, Well-Kept Gardens Die By Pacifism was originally published on 21 April 2009. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was The Sin of Underconfidence, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
Sequence reruns are a community-driven effort. You can participate by re-reading the sequence post, discussing it here, posting the next day's sequence reruns post, or summarizing forthcoming articles on the wiki. Go here for more details, or to have meta discussions about the Rerunning the Sequences series.