The touch is basically a prepaid phone with no phone chip. They could add that phone chip and absorb the margin hit through scale in China, etc. Bound to happen sooner or later.
The nano is a redesign away from assaulting the global watch market (over $40 bln this year).
The shuffle, I could seem them innovating the form factor, why not abstract it right into the earbuds.
The classic is dead, growth wise so they can keep selling it but don't think it'd shock anyone if they shut it down tomorrow.