There's a few upsides. First, it plugs into my workflow really well. If I have some silly idea for a site I can just register the domain name, point it at this app, and drop some content into a text box and it's live, with the possibility of writing content in Markdown, Textile, or any of the other markup languages that Gollum supports.

Second, and really more importantly, it let's my wife easily update pages that she cares about. For example, one of the microsites hosted on there is our wedding website. If she wants to change or add something she can do that without having to muck around with text editors and git and stuff. And if one of us messes up, it's easy to revert back to a previous version, since it's just Git.