Wow, I disappear for a few days and when I next look there's all this new info. Thanks to Ulthwithian for the helpful summary!
Ceilidh Hall as the Celtic UB is... hmm... different. At least it's not a Dun I guess. And it does give a nod to an important part of modern Celtic culture
I was kind of hoping they would have a faith-boosting stone circle UI, but I guess that's redundant with their UA.
I can't help but be slightly disappointed that the Austrian UB isn't a Concert Hall or something music-related (Mozart, ffs!) but coffee house culture is another important contribution they have made to western society.
The new luxuries/resources sound cool. My guess for Copper (if it's not a new strategic resource, which seems unlikely) is that it's going to be a production-related bonus resource, perhaps specifically affecting unit production.
The new City-States all sound like good choices as well. Yay for Zurich, Manila and Jakarta (although I guess the latter means we're not going to see Indonesia/Majapahit any time soon).
Embassies sound a bit disappointing. Unless 'show capitals' means 'can view capital'... but perhaps that would be a touch OP.
And finally, major yays for the extension of the Classical Era!