It's very nice. You can use your fav editor and update pages, then push the changes back up and they appear in the wiki.

With a few plugins and some hacking, you can get vim to just browse the wiki too. (I'm currently working on getting my scripts for this into a state that is useful).

Unrelated - there are some plugins to use the github api to browse tickets in vim too.

(note not all of these workflows make sense as a primary way of using them, but they are still useful at times).