Here's an interview with producer Charles de Lauzirika about the new cut:
http://www.chud.com/index.php?type=interviews&id=11285In terms of footage that didn't make it into the original...
That's in the new Final Cut? There's a lot of nuance. It's a lot of moments that kind of flesh things out or are closer to what was originally intended. For instance, the new unicorn dream sequence is the original cut of that sequence. It's not just Deckard at a piano, arbitrary dissolve to the unicorn, arbitrary dissolve back. It's him at the piano, to a close-up of him thinking and staring off into space, we go to the forest, the unicorn eventually runs in, he reacts to it. It's more in his head. It's not what they could do in '92, easy and cheap because that's all they had. We found the original footage, we found the original cut, conformed it with the negative, so it's more of a vision in his head. The sound design is totally different. It's the moment that Ridley wanted, not the moment he had to concede to back in '92. Things like that.
There are several new VFX tweaks and changes, enhancements that fix a lot of errors. Most notably, there's the scene where Batty dies and lets go of the dove, we go from dark, rainy, grungy we cut to blue sky, aluminum corrugated sci-fi tubes. So it's now a really gritty, grungy matte painting that's beautiful...it's like a hybrid of what would be done in '82 that was actually shot in 2019. It's really clean and elegant, we've got the same dove to lock onto through the cut.
More than that, though, there's also going to be a special briefcase collection's edition containing every single substate of the film: the US theatrical version, the home video/international version, the 1992 "Director's Cut", the legendary workprint version, and-as the interview above mentions-a whopping forty-seven minutes of deleted scenes cut together with an alternate version of the narration, so it's almost like a sixth version of the film. And lots of nerdy souvenir crap. I'm toying with the idea of buying it and taking a week off work to have my way with it...
http://tinyurl.com/3bu8s9