Noise cancellation is an established technology, but it tends only to be really effective in very specific or controlled environments. You can cancel a lot of prop noise in a small plane because you know the cabin dynamics, but cancelling generic noise in a generic car cabin would be an entirely different kettle of fish.

I believe that some auto manufacturers are researching this (maybe there are even early systems on the market, I haven't checked recently) but they have an advantage because they're designing for a specific model and audio system.

Rob