It's neat when something comes into focus all of a sudden. I read "The Death of the 'Comments' Section. RIP" by Steve Mallett and I finally figured out why (instead of how) to use Trackback. Until I read the article I didn't really realize what need more specifically that Trackback filled... now I do. Now since many people have weblogs they aren't posting comments as much...they'll just make an entry in their 'blog that links back to what they're commenting about. Trackback can assemble those together. Mallett also links it up with community, which is less than or equal to 150 people. Movable Type has Trackback built-in and I can use that where I teach (with a Movable Type 'blog for my students) and I can also add Trackback support to Blosxom (which runs this 'blog). Rael also did a comment hack to Trackback to add comments to Blosxom. It's neat to see how this stuff is all evolving and even better when a bunch of things click into place and suddenly make sense.