PG mentioned somewhere else that there's a 24 hour timer, after which point the pending comment is deleted -- and one can post again. It does sound to me as a rather steep penalty for wandering off the beaten path. One would be free to self-censor of course, which I suppose is the intention.

We'll see how it goes, but it does sound like it'll likely work against HN being somewhat heterogeneous, and (even more) towards group-think.