So I was a latecomer to the whole iPod thing, being gifted a third generation iPod Nano almost two years ago. I like it; it's not big and bulky, and yet videos are totally watchable on the crisp little 2" screen, should the urge strike you. What I mostly used it for was listening to music in the car, connected by its umbilical to the head unit in the dash.
I noticed the evolution of the iPod Nano had turned it into a seriously handy little Swiss army knife of a gizmo by its fifth iteration: It had added a radio and a video camera and a microphone and so on. I thought it might be a worthwhile upgrade, but I wasn't really unhappy with the one I had. The video camera might be neat if I needed to take a picture of something while driving, but...
Then Apple forced my hand. They announced the newest version of the Nano this fall, and it had lost video recording and playback which, while disappointing, was no dealbreaker. But they had also fitted it up with a teeny 1.5" multitouch display, and that made it completely useless for me.
Let me make a little digression: Younger readers might not realize this, but domestic American automobiles used to have a singular triumph of ergonomic engineering: The headlight switch. In pretty much every American car, by whatever maker, was a round knob on the dashboard just to the left of the steering wheel. Pulling it out one click turned on the parking lights and pulling it out all the way turned on the headlights. Rotating it clockwise brightened the instrument panel lights and turning it all the way clockwise turned on the overhead dome light. Genius. It could be operated totally by feel and it worked the same way in your car, your drunk friend's car, or a rental car on a dark and rainy night far from home. Random agglomerations of buttons and rotary switches placed anywhere the styling department could find room are no improvement.
The iPod's click wheel is like this. With audible and tactile feedback, I can skip songs, go back, fiddle with the volume or whatever, all without having to take my eyes off the road to select menus or read screens. Because the iPod has a long side and a short side, I don't even need to look down to see how it's oriented in my hand to know which part of the click wheel is the "top".
The newest Nano has none of this, and I don't think it's any kind of improvement in the car audio role for which I use my iPod. Now if I wanted to upgrade, I was going to need to either shop used or find New Old Stock, and if I wanted a good one, I'd better get cracking. It was quickly apparent that I was not the only one who felt this way, as used 5th Gen Nanos rapidly started selling for as much or more than new 6th Gen units on Amazon. I wound up getting a factory refurb directly from Apple, since apparently they hadn't gotten the word on the desirability of the older units and were selling them for less than the new ones.
It arrived, a 16GB black unit, and it is handier than a pocket on a shirt. Not much bigger than a stick of gum and it holds thousands of songs, takes home movies, and can play back TV episodes. Neat. And I can operate it without taking my eyes off the road.