I'm going to make the opposite argument. I think the current batch of Start Menu, dock, and panel launchers represent the product of continuous refinement. I honestly question whether the interface can truly be improved (versus made different) for current desktop interfaces. By current desktop interfaces, I mean a monitor, mouse, and keyboard. Right now, there no interface better for accomplishing real work on a computer.

Tablets and future, immersive, physically interactive interfaces (e.g. "virtual reality") will certainly be different, but I don't see why we should completely warp our well-established paradigms of interacting with current technology.

Incidentally, the greatest sin I see is that they seem to be keeping the Start Menu concept, but they're hiding it!