ckknick, it's tough to know whether this will extend or not. It's certainly doing phenomenal business, but Roundabout has an issue in that they owe their subscribers at least one more Broadway show this season (they currently only have 2) and all of their theaters are booked. Meaning basically either "Cabaret" is going to have to close or "Beautiful" is going to have to move or close (or they'll have to find some other Broadway theater to rent for the Spring, which is unlikely given how many shows are already booked).
Yes, they do owe their subscribers another Broadway production this season as well as another Off-Broadway. Subscriptions have already been sold for 4 shows on Broadway and 3 Off-Broadway.
Yes, if that's the case, they actually need 2 more Broadway shows then and the American Airlines is already booked until July, so those shows will have to be either at Studio 54 or the Sondheim (again, unless something else closes and they can rent out another theater).
I emailed Roumdabout because my mom is a subscriber and was wondering, and they emailed back: "Thanks for your email. We have two more shows to be announced, one at Laura Pels ad one at Studio 54. Cabaret is currently scheduled to close January 4th. Nothing has been said about extending beyond that."
That says "An Invitation from Our Friends," TalkinLoud and it isn't indicated on their webpage that it is a Roundabout production, so I'm guessing it's not part of a subscriber package.