Did you see read this interview ? A few questions are a partly answered :

http://www.gameinformer.com/b/features/archive/2015/06/19/yu-suzuki-shenmue-iii-interview-e3-2015.aspx?utm_content=buffer1500d&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

"Shenmue was a very revolutionary and influential game when it was released on Dreamcast. A lot has changed in the games industry since then. How does the team work to make a game just as revolutionary so long after the original?
It’s all about the new challenges with me, and I definitely want to try these new things. Of course, it’s going to come down to the funding and how much we’re going to be able to spend on Shenmue III, but if we get to that point, I believe it will be just as revolutionary as the ones before."

So it's seems it doesn't have a budget secured. But maybe more funders would come after such hype.

Thanks Jibby and SheepheadCG. It should be pretty cool ! It would be super cool if he'd show us some part of shenmue 3 from dreamcast that were a bit developped, but he probably won't.