First of all, special thanks goes to Dromaeosaur for coming out of nowhere like an angel. My posting for this week (and maybe even next week) will be very, very limited, so Drom just showing up like that is a miracle.
EDIT: Wow. I can't believe how stupid I was. I just came back to this post today and realized (with some help from Eternocte) that this is NOT the next game Quantic Dream is working on, it's just a tech demo. It even says right here in a Gamespot article that it "is a concept only and is not taken from any software currently in development". It also clearly states this in big, eye-catching letters in the video. I must have blanked out during that part. My bad. Thanks, 'Nocte.
Since I don't have time to put a pony memes together (sorry everyone), here's a tech released by Quantic Dream (developer of Heavy Rain) that shows off a lot but reveals very little about what the dev team is up to.