3D interfaces may eventually be the future, but I don't think this version is it. First of all, it's gonna eat up your desktop space like crazy, for what advantage really? Wow factor? That wears out quickly.
Which brings me to my next point; there has been technology to do a variety of different types of 3D desktops for a while now, but it hasn't been pursued because so far going 3D doesn't provide much in the way of practical advantages for most applications. If you're browsing the web and reading email, 3D is doing nothing for you except "Oh man isn't this cool?"
The one place where it makes sense is where you are dealing with actual 3D objects, like 3D printing and CAD/CAM software.