Nice article. I love how some of the most widely used stuff now days is just something random that some developer at the time thought up whimsically.
There's a video somewhere of Mark Zuckerberg and some co-workers discussing ideas about Facebook (in it's earliest days), and in the video they are trying to decide on what options should be available under the relationship field, one guy says something like: "I feel like we should make it possible to say that.. like you're not in a relationship per se, but nor are you free, like it's complicated..."