Better speeds and no caps, generally.
A lot of teens, through to about 26 don't watch TV, they just watch streamed content on their computer...
Edit: As to the Nano, I don't need a screen. When I am using my iPhone, it is 99.9% for audio. I listen to a couple of video podcasts, but the iPhone usually sits in my pocket or in the cupholder in the car and I just listen to the audio - I'd download audio only versions, if they were available...