So, thousands of years ago the wheel was invented. Most people, on discovering this new fangled device immediately began thinking up new things that can be done with said wheel, new applications for the round-shape, new wheel based industries and so on. So far nobodies invented an improvement on the basic wheel shape, someone came out with 'ball' (a kind of hyper-wheel) but ball turned out to not quite fit the same markets that wheels are useful for.
Since the invention of wheel we now have wheels and disks performing all sorts of vital functions, not all of them even roll-related really, like frisbies and cogs for instance... all these new applications and addaptions of your basic wheel-shape have come about from the invention of the wheel, but it can't really be argued that any of them are anything less than a development of the basic wheel idea (although some of these applications aren't really just about rolling things about anymore). We have advanced ideas like the catapillar track, but that's just lost of wheels arranged in a line and wrapped in a chunky belt.
So, not saying what tommorow might bring, there could well be some hot new upstart challenger to the wheel... just saying that wheel even today tends to draw people into thinking of new wheel based applications and things that can be done with the wheel or wheel-shapes instead of sitting around thinking up completely new ways of rolling things around that is not a wheel.
Mind you there are concepts out there, like super-lube (slide anything over anything, who'd need wheels anymore), or hover technology... In my humble opinion however, it's all about the wheel going forward. Because wheel is such a great improvement on what we had before (drag-bricks or whatever).