From the way they talked about it at E3, the first game is basically just midgard or related. They mention not knowing just how many games the series will be in the end due to the added material.
They talk about that here.
I don't think we'll see the end of this new series for several years now. I can see it easily being a trilogy or better.
Maybe, but we don't know. Square is being tight lipped about it and refuses to mention anything about it being episodic anymore.
The only thing I'm sure of is that they are currently avoiding the subject.
Like I said, there was a fair amount of fan backlash to the idea, and they may have backtracked on it. We aren't sure, and I have my doubts even they know how it will be released at this point.
Kotaku is a political blog pretending to be games journalism. They frequently fuck up information like this and often talk out their asses about things they clearly know nothing about. Their editing staff has no concept of fact checking. I have no respect for them as a publication, and don't trust anything they publish. In fact, I feel a little dirty about giving them a page view by checking that link you posted.
First of all, that article is flat out wrong about Midigard being 5-10% of the original game.
Midigard is roughly the first half of Final Fantasy VII. You leave at the end of Disk 1.
Disk 2 and 3 together are actually only slightly more information than what is on Disk 1 believe it or not. Neither of the latter two disks is anywhere near full. What is on those two disks is actually only slightly more than what would fit on one disk. Disk 1 uses nearly all the available space on the disk.
All of Final Fantasy VII is roughly 45 hours of game if you're just doing the main quest and a few side quests, maybe 75 if you're going for 100%. You leave Midigard and end Disk 1 at around 20 hours in.
Yes, it is possible to put a hundred hours into the game, but that's not normal. Most people will finish it in somewhere around 45 to 75 hours.
The reason the other disks seem like more of the game percentage wise than they are is because that's where most of the side activities are and it pads things out a bit. Things like Chocobo breeding, racing, the mini games at the Golden Saucer, etc, all that stuff is on the second disk. The third is mostly endgame stuff.
Also, the fact that there is an overworld and the environments are more varied contributes to the latter part feeling "bigger" when it is actually only slightly so. You spend a lot of time going from place to place in the latter part of the game, where as Midigard is a fairly centralized location that uses a hub and most areas within it look visually similar.
The first part of the Final Fantasy VII remake being the Midigard segment fits with what I said and actually suggests that it being a two part game is plausible.