I personally don't like the Xbox360 and I don't plan on buying one.
I would however buy a home theater system that was Natal powered eg a remoteless system, allowing for the changing of volume and channel with a hand gesture.
what other applications can you see for this technology apart from gaming?

I can see some medical institutions using Natal for physiotherapy, and of course research institutes could use it for biomechanics and sensory perception studies.

As for Joe Sixpack, I think the only significant things will be home theatre and gaming.