Channel factors and LiveJournal
I never cared much about the distinction between Blogger and LiveJournal--they're both hosted services for publishing blogs. (Or "livejournals," if you go to Berkeley.) But LiveJournal-managed sites always had rampant comments, something that I was honestly a little jealous of. So much visible community-building.Today I learned why. While Blogger doesn't automatically tell people when others have commented on their comments (and in fact, I tend to manually email replies to people), LiveJournal lets you comment on a comment right in your email client. So easy. Ross and Nisbett would be proud of the channel factor.
Comments
I do think that livejournal's automatic emailing of comment notification is a very important part of encouraging long comment-discussions. I can imagine several other different features that would also be just as (or more) useful though: one, being able to see on the site a list of most recent replies to your comments or posts would serve about the same purpose as email notification; it would just require using a web browser to get that information instead of interleaving it with the rest of your email. Two, being able to subscribe to particular peoples' "comment stream" --- like if I could aggregate all comments made anywhere by any of my friends --- would just be a great way of discovering conversations that I might be interested in following.