Depends on what 3D Desktop effects you're talking about. Zooming is quite nice and I could see it being quite useful to a lot of people. Wobbly windows on the other hand fall under pretty until you get annoyed and turn it off.

I've yet to see a single usability report come out with facts showing a 3D UI is more effective at ANYTHING (on any platform).

I'll save my clock cycles for something more useful.

It seems that when the shading added to radio buttons to make you believe that the button was depressed, was the first 3d effect used wisely.

The 3d software today is not application sensitive to help 3d illusions may be the reason you don't like the 3d software.

I am sure that when digital displays go analog such as in the National Instrument software, you would appreciate the 3d effects on analog instrument displays.

And then there are games that had many good 3d pictures.

We have such fast computers these days, so I guess we may as well waste our clock cycles on things like a 3D desktop. Personally, I prefer no desktop at all.