Icons vs. 3D spaces

I thought it was interesting how the operating systems we use mostly make use of icons. There have been multiple attempts to set a 3D interface on top of an OS such as the 3DNA UI seen here. Users can decorate their space with move around the room to choose their tasks. Pretty interesting, but not as efficient as having all your icons laid out evenly for you. Microsoft just patented something called "Offer 3D task method and tool of the computer interfaces of spaces". It will be interesting to see what they do with it. Here's a youtube video of another attempt called Bumptop 3DDesktop: http://www.youtube.com/watch?v=M0ODskdEPnQ