RE: the whole multi-part thing - it's easy to immediately assume SE will opt for the biggest money spinner available to them and go all episodic. At this point though, one dubiously-translated sentence isn't enough info to start flailing about uncontrollably and start shouting profanities at strangers in the street.
In fact, there was a similar game that came out a while back that was split into 'multiple parts', if only because storage constraints meant devs had to split big games into separate discs. I'd even go so far as to say that each disc 'provided its own unique experience' in terms of both story and gameplay.
My point is, it could just as easily be a way to emulate the feel of that 'please insert disc 2' achievement I felt from the original. Just a thought.
Or, it could totally be a ten part thing that lasts three years with each bit costing the same as a full game. Who knows!
EDIT: I am aware there's been an interview. It still hasn't been explicitly stated sections will be sold separately. We'll see.
While I'm here, I might as well share a couple of thoughts about the thing.
They seem to be taking a few unexpected liberties with design (i.e Barret's new shades, and the fact that despite the buster sword thing being quite a huge point in CC, they've reverted to the original design for that). Minor things. I'm cool with this, it's all artistic license as long as it doesn't screw with anything major. We'll see.
What I'm slightly more concerned about is the overall colour (or large lack of) in the trailer. There is a worrying trend with blockbusters of a similar ilk to suck all the colour out of everything to make things look 'cinematic'. To me, it just makes everything look washed out. I get that maybe Midgar is dark and so that particular section's been done on purpose. And yeah maybe a bright purple uniform and blindingly orange hair won't work as well today as it did in the 90s. But annoyingly, they seem to have stolen the art direction from XV, and I'm not sure if anyone at SE has realised that they're separate games. We'll see.
But that's the main gripe I have with the trailer so far. Looks as though they've copy-pasted FFXV and stuck some fresh models in over the top. Actually, I wouldn't be surprised if that was part of the reason for switching engines and all the development complications etc. The battle effects just look way, way over the top. I'm actually personally really excited by XV, but what works for one won't necessarily work for the other. Again, we'll see.