I own a Nano 3rd generation and now also one of the 4, because I have the display of ancient unfortunately destroyed ....
But, for that I have a direct comparison. The old man is now in the car.
The new one is really very thin, but it becomes a bit unwieldy. It has literally nothing in his hand. He is of the dimensions here so similar to the Nano 3G, but the fact that it tapers to the edges, he more much flatter. I found that the elderly better.
Likewise, the clickwheel is sensitive. It is difficult to choose something from the menu to get to quickly in the row above or below. Ohen Keylock iPod is take in hand, to adjust something, if only the volume.
Cover Flow: can not be switched off, unfortunately. In the evening in bed, listening to music and then use the iPod blind is hardly possible: Once the iPod moves / is held at an angle, it switches to Cover Flow. So volume change is not possible, only turning back. For the transition to wide-screen is better when viewing videos.
Overall, the new presentation of played objects is beautiful. The display looks clear.
Biggest plus is for me (besides the 16GB), that the reverse is now also as the front. Keeping the old Nano scratch-free without the protective cover is impossible.
Unfortunately (Kenwood adapter with me for the car radio) invites the novelty of many accessories no longer on. Too bad.
Shake feature you tried this, but that's it. Mostly you have to shake tidy. In the gym the first question: Isser already broken? And that's how it looks, shaking as if something does not work ...
Genius is ansich not bad, but he does not manage to really keep the genre apart. Or heard Atze Schröder to the direction of the Fugees? I do not think ... so as not Shake = really necessary.
Is it good or not? Yes and no. As successors of the 3rd generation to little better than brand new already due to the lower price a recommendation. But there is the 3rd generation 16GB and the display, I would immediately replace. That's why only 3 stars!