I like the UI of Discourse, it's certainly more updated than the 90's forum look most forum sites have.

It looks like it has a lot of potential, but it certainly is a great shift away from what we have here.

I hope people are not too frightened when they have to "learn" a whole new UI.

The one thing I'm immediatelly missing at Discourse (or I'm just too stupid to notice) is some sort of bread crumbs to go back to the categories.

You can only click on Discourse at the top, which brings me to the main page in the popular section, which just shows everything.