At the same time we were discussing sorting. Everything is chronological, but people might want to see popular things. Is it popular because people vote up on it or because lots of people read it? Of course, lots of places weight these today (like Reddit), so that was discussed.
Third, given the relatively higher traffic we're seeing on video content (duh, Youtube generation), adding a second row of video thumbs to the front page makes sense. I also rolled the idea in my head of adding a little randomness into this section, to get more mileage out of old videos.
Resulting conclusion: we don't care about sorting, we care about clicks (duh, again).
In other words, I shouldn't be looking for how to weight the sort order of videos and stories by popularity, which is the first obvious thing to do. What I need to ask is "which videos, placed in this section on this page, will have the highest chance of being clicked?" The first thought I had going down this road is the two obvious classes of users: new and existing. New users need to get caught, so show them something flashy. Show new users pillar content, a nice video introducing the site, and generally popular things. Existing users, most easily identified by having them log in, have already had the candy and now they want some potatoes. Show them new stuff, things being discussed, and things based on their preferences, if you've got that kind of thing set up.
Another consideration is the predictability of item selection. If I'm going to show eight videos on the front page, why should I pick eight of them? Why don't I pick sixteen and alternate? Not back and forth, but moderately random selections each page load. Really good videos might always be there, and "bottom of the top" videos might show up just now and then. For frequently anonymous users, who think "I'm not sure I like this site enough to sign up yet," get a better range of videos they're exposed to and hopefully more inclined to stick around and sign up.
In the opposite manner, can we figure out what to start excluding? After seeing the same story twenty times and not clicking on it, maybe you stop showing it to them. That space could be used for something they might be interested in.
Of course, I know I'm not inventing everything here, but I wonder if anything is a fresh idea. Obviously plenty of sites are learning to keep popular things around. Is anyone hiding ignored items? I don't know if the things I'm talking about are just "things some people are doing" or if there are real maths behind it and hard terms and concepts I can study to do it right. Hopefully, I'll be able to write more about solid results soon.