you have to agree, the multi-touch interface is a joy to use.
I only played with it for about an hour in total (a few consecutive trips to drool over the iPhone and the iPod Touch), but it felt natural. Seems that they really did invest a lot of energy in it's development, and "wasting" it just for an iPod or a phone seems like a bit of a waste to me. I can immagine Apple doing something bigger and better with it.
Multi-touch iMacs maybe ?