Munster reported a few days ago that of the iPods sold during Black Friday (unofficially), 38% were nanos, 19% classics, and 19% touches. If that's even close, it shows that there's a market for each type, and I hope Apple keeps offering all three.
For me, I have a new nano (for most travelling), and a classic. I'm not interested in the touch - I like the nano/classic interface just fine. Then again, I'm a dinosaur - I've never had a cell phone.