those aren't really 3D desktops, they just use 3Dish graphics in the transitions. imagine if instead your GUI was a small 3D world that is a nice apartment with all the trappings: bedrooms, bathrooms, a home-office, any other room you might like. ebooks that look like physical books on physical bookshelves or strewn about the coffee table of your living room, email in physical-like envelopes, where unread mail is in a sealed envelope, and read mail is in a torn open envelope, documents in those hanging folders in physical-like drawers with physical-like locks and physical-like keys (though requiring very real passwords to decrypt). think of what a nice looking 3D GUI would look like, use you imagination. maybe someone will have the ability to create it, a sufficiently powerful computer to run it, and the fancy to want it.