Allan Grinshtein from LayerVault:

Designing honestly means recognizing that things you can do with screens and input devices can’t be done with physical objects — more importantly that we shouldn’t try copying them. It takes too much for granted. Can you imagine your pristine iPhone built into the body of an antique telephone handset? Is that beautiful design?

It’s a great analogy.

The answer, of course, would be that it would be beautiful design, but it wouldn’t be the right thing to do for that device.