The problem with all of these 'flying car' stories is the vehicles in question never meet the public's understanding of what a flying should/will be. In a nutshell, it needs to have some kind of anti-gravity functionality that allows it to hover.

For greater clarifty, but so as not to limit the generality of the foregoing, see -

http://www.youtube.com/watch?v=bWST1_xO6PY