"Are they using the stage version of the original finale, as indicated by GetUp&LiveIt ('the principals repeated their lines referencing their blindness to the outside world") or the version used on the original cast recording, as indicated by Alix ("the main characters each reprising a bit of their songs")?"
Oh, it was probably lines of dialogue, like GetUp&LiveIt said. I can't say I recall exactly; I was a bit distracted by the Nazi raid going on below. The only one I know for certain is that Sally sang a couple lines of "Cabaret." I didn't realize the original cast recording was different than the actual onstage ending in the original production, though. Interesting. Broadway Stud, do you recall, since you saw it most recently?
Thinking about this production more over the past week and a half, I think my main issue with it was that it was a tad too "on the nose," as elphaba.scares.me put it. Two examples (aside from the ending/"If You Could See Her") come to mind: When Herr Schultz and Cliff first meet and Schultz wishes Cliff "mazel," and Cliff doesn't know what this means, Schultz usually replies "Yiddish--it means luck." In this production (at least in the first preview, when I saw it), the line was "Jewish--it means luck." Then, during the first "Tomorrow Belongs to Me," the Emcee grabbed Cliff's copy of Mein Kampf, which had already been acknowledged and discussed at that point, before starting to silently read/look through it. When he first grabbed the book, he held it up and moved it around to make sure every part of the audience could see what it was, like a teacher reading aloud to a group of kids and making sure everyone can see the illustrations. Minor things, but both moments took me out of the show a bit. It just seemed a little too obvious that the director was making sure everyone was getting the message, which then makes the message less powerful, in my opinion.
As for the ending, I think I liked it overall. I have mixed feelings about it, but I appreciate that it was a different take, at least, and actually quite liked that the focus at the end was on a Kit Kat Girl with no lines rather than one of the main characters. The "If You Could See Her" mask reveal felt at the moment like the ultimate way-too-on-the-nose choice, but it was necessary to set up the ending.
My other issue with the production was "Cabaret," which was too cheery for me. It didn't seem to match the tone of the rest of the second act. It sort of felt to me like the director was going for a more Liza-esque version of the song just for the sake of not copying the more tragic take that's usually performed today. I personally don't think it works as well onstage. Barrett sang the crap out of it, though.
Having said all that, I really did enjoy this production and would encourage anyone who can get there to go. But I absolutely worship the Mendes/Marshall version, and I don't think anything could top it for me.