My blog does not have an edit button for people who are not me. This means it takes a bunch of work to fix a typo, for example: you’d have to tell me about it, describing where the typo is, somehow, and then I would have to go find the spot, and make the change. In practice, this pretty much doesn’t happen.
Wikipedia has edit buttons on everything, and so does github. I’m not entirely sure what is best between allow-all-edits-immediately and require-review-for-all-edits. Some mix is also possible, I guess. Wikipedia has ways to lock down articles, and must have corresponding permission systems for who can do/undo that. Github lets you give other people full edit permissions, so you can spread the editor pool at least. Git by itself can support even more fine-grained control, I believe.
I’d like to move my blog to something git-backed, like github pages. It’s a little work, but you can put an edit button on the rendered HTML views shown by github pages too. Advanced R has a beautiful “Edit this page” button on every page. Three.js has one in their documentation. Eric points out Ben’s blog as well, and also the trouble with comments.
So: that solves that.