I like and support the idea, but I'm not confident that it should be the default (Edit: Or am I?). I think threads around a week old still get comments fairly often (correct me if I'm wrong) and this might make it a bit harder for new posts to get exposure. I'm also not confident that it shouldn't be the default though, and I'm thinking of reasons it should as I type this.
1) People that visit the discussion page (for the first time and otherwise) will see active conversations. 2) Interesting things will stay at the top longer. 3) No need for new posts to bring new information to past posts (already mentioned).
I don't feel like deleting this comment, but I think these benefits outweigh the problems I mentioned earlier. It would make it a bit less "blog-like" though (it is a bit forum-like as it is, though, and this doesn't appear to be a problem).
I think it's perfectly okay for the main section to be blog-like and the discussion section to be forum-like.
Pretty much agree that yes, there are some consequences to making it default, but positive consequences outweigh negative ones.
The latest SMBC made me laugh a bit, so I thought I'd bring extra LessWrong attention to it.
I don't know if pointing out the subject of the comic in advance will make it more or less funny. Knowing that might be more data regarding that recent study claiming that spoilers don't actually spoil stuff...