Yeah, they discussed this on a Tek episode before upgrading it. The forum was formerly powered by some kind of Drupal stuff, and now it uses a customized version of Discourse. As I understand it they just tweaked it to work with the existing Drupal authentication system, but maybe @wendell can provide more specifics.
So the "Categories" tab didn't exist at all in normal Discourse? Or you improved an existing thing? Either way that's freakin' awesome, props to you and Wendell for pulling that off.
Well the category tab did exist. However wenn we tranfered over from the old forum, there basicly was no category structure at all. Everything had to be re-organized, and that is basicly one of the things i have done. I made all the main and sub categories, and moved everything to the right place, adding certain new categories etc etc.
Not for the things that i have done to the forum. I did just most of the re-organizing part of the forum. But i think that if you just start with Discourse its pretty straight forward.