Black Butler: Book of the Atlantic is a Spring 2017 movie[in Japan]
Not sure if this is the correct forum for this [and given how complicated FUNimation's relationship with Aniplex is these days, no guarantee of FUNimation acquiring it]
Comes out Spring 2017
This is what I've been waiting for years for.
(Also, even if Aniplex takes it, they need to get FUNi to dub it with the same cast, because yes.)
I have been thinking about getting into this show.
You should, you definitely should. It's a lot more than it looks like, actually. You might want to watch just episodes 1-6 of the original anime, and then ship to Book of Circus. (If you want the plot in-between, get manga vol.s 4 and 5, the anime version for that part isn't great).
Book of Circus covers vol. 6-8, Book of Murder covers the next 3, this movie is the next arc after that. If you don't want to wait, go ahead and read the manga - up to 21 are out in English, and it's really good. It goes places you don't expect it to.
…the latest volume actually had a bit in the authors' notes where the mangaka's assitant asked her, "When's the last time we were drawing fancy tea sets and chandeliers?" and she didn't know what to say. ^_^;