On a Friday afternoon, shortly after Twitter's list functionality was rolled out, I had a thought.
I didn't like the fact that Twitter lists were static, and required hands-on maintenance to keep current. We've played that game before with blogrolls, so I think we all know where it ends: with a bunch of infrequently-updated, largely meaningless lists that are widely ignored.
I also didn't like that Twitter lists (as they were being created at the time, at least) were largely topical. People's tweets are as eclectic as the people themselves, so a "music" Twitter list might have about half music content and about half...well, everything else. Poor user experience.
But what if there was a list that showed who that "music" guy you follow on Twitter was paying attention to? And what if that list was automatically updated to reflect the changes in that guy's attention, without him having to do anything? There could be something there.
So I talked Kevin Marshall into writing the actual code, and we soon had "conversationlists." Some people thought they were cool and started using them. A couple of days later Fred Wilson said they were cool and more people started using them. Then Evan Williams (you know, the CEO of Twitter) and Techcrunch said they were cool and even more people started using them.
Not bad for an idea and a day of coding.
Read the blog post that addresses the underlying issues.