You need to let this die already. They're not waiting. There
will not be a sequel or a remake/reboot. Period.
http://www.telegraph.co.uk/film/back...bert-zemeckis/
http://www.usatoday.com/story/life/e...ppen/77531184/
They know a new movie would have raked in gazillions of dollars. They also know it wouldn't have even remotely held a candle to the originals. If the Bobs haven't been tempted by cash by now, they won't be. The end. (It's called artistic integrity. They have it.)
You can also bet that the Bobs will be smart enough to lawyer-engineer their estates to retain ownership of the movies after their death, too.
We will never, ever see a new BTTF movie. And that makes me incredibly happy.