The big question is: can we build a whole brain. Will we in the coming 100 years ever understand all the functions of the brain and how they interact. There is a possibility that there is some kind of limit where we cannot see further without discovering a whole new field of science.
I am planning on doing a technical AI master. One part of me hopes we get there and build a full human AI and the other part doesn't. Like the movie Transcendence correctly describes is that an AI brain can lose all it's boundaries, we humans are bound to a body, we cannot think more than X steps in front, we cannot photographically remember ever page in a book and at the same time index it for nanosecond retrieval, and that's is what keeps us humans contained and forces us to think and rethink about our decisions (being wise).