Not exactly untranslated, the episode one subs were:
After that however, it was referred to as "Looking Glass City" until the show's end (when the characters pronounce it as Kyoto).
Also,
the episode descriptions do use "Looking Glass City" as a name a lot.
Discotek is doing the English BD/DVD release and I don't think they'll change the subs (if they didn't release it already, last I've read something about it was in March on their Facebook page).