I do not believe flying cars will ever become a "common" thing for the average person but who knows. I think they sound incredibly taxing on the environment, so that's definitely a negative and a factor against their use. 100 years from now, I think travel will be entirely different. It has to change in order to save the environment and the world. Mass transit,
hydroelectric/air powered/electric cars will probably be common and more people will probably walk/bike/carpool places. At least that's the hope.
I commented on
Austin's blog.