I agree that debate is a lost art, and politics has become consumerized just like everything else; whoever advertises the most and trashes their opponent the best seems to win.
Unfortunately, I'm not sure that in our current atmosphere that this will ever change. It may be more of a function of the type of people that are being attracted to run for office, than the attitudes of the public. So the only solution may be for some principled individuals to rise to power and set an example. (Libertarians, while extremist, are a good example of the principled sort.)