With modern graphics cards, surely the resources for 3D desktops are already there? I just don't see why we should stick with 2D vector graphics, when we could directly move to 3D. The rest of the computing world is doing just that right now. MacOS has done it a few years back and now Linux and Windows are following. As usual the Windows version seems to be the worst design, but just imagine how cool it would be to bring RISC OS' effecient and user-friendly GUI to the third dimension.