The cartoon doesn't say when "tomorrow" is supposed to be, but fifty years on it's pretty clear that very little progress has been made towards the concepts depicted in the cartoon. The highways of 2008 look much like the highways of 1958, with the only changes being some improvements in design standards and construction techniques. The sweeping cantilevered bridges, self-guided vehicles and massive construction machines depicted in this cartoon are no closer to reality today than they were fifty years ago.
Interestingly, the cartoon clearly does not anticipate the one thing that, in retrospect, has been the biggest shortcoming of the highway: ever-increasing traffic congestion. The cartoon's animations generally depict highways that are practically deserted; of course, in 2008, our highways are anything but. Nor does the cartoon foresee air pollution, dependence on increasingly-scarce foreign fossil fuels, skyrocketing obesity rates or other negative automobile-related externalities as being problems in the easy-motoring future.
The cartoon also makes some predictions that, in retrospect, are spectacularly wrong. It claims, for example, that "advances in technology will give us more time for leisure in tomorrow's living." Of course, we know that the opposite has happened. It also depicts father going to work while mother and son go shopping: a family dynamic long-since disappeared in today's two-income world.
However, I can't help but enjoy the 1950s spirit of optimism conveyed by this cartoon: a belief that all things are possible through technology and that its advances can only bring us a better way of life. Today this view seems rather naive. Perhaps that's why it feels so refreshing.