I think that the iPod touch will move over to the iPad family and the iPod nano will be the only iPod left but it will also evolve to be more than what it is. It will become a control panel, a camera a messenger or reminder for what you do (part of reminders) and more. the iPod touch will be larger, about half the size of the iPad. thats my prediction.
Coming to an apple store near you very soon! What a great way to get some nerd core credibility. Now you can have a more secure way to have your nano with you all of the time. Now if only someone will make a necklace mount for my iPad! I could rock it Flavor Flav style!