Earlier quoted context omitted.
Perhaps "Top 10 most-commented posts" would be interesting as well?
That's a lot harder to do -- I can get away with scraping the front page right now because highly voted posts are likely to be on the front page for most of their vote-getting lifetime, but that argument probably doesn't hold about highly commented posts.
This would hinge on the frequency of all comments to the site and having your scraping interval be less than the difference of the most recent comment and last comment displayed on /newcomments.
I think it'd just be really great to have another view into "Most active discussions".