Formula 1 has always sought to push the boundaries of design, to get around the rules. millencolin is right in that the restrictions are such that major innovations are pretty much impossible.
Because of this, F1 is in a real state of "optimisation", where the interactions of all components with their neighbours are being considered. Ferrari are the real masters of this in the whole car, and that's why they've been winning so much recently.
It means that superficially the cars all look the same, and don't change from year to year. But you go back and look at the 2000 Ferrari, and compare it with the current car...