I got a 6G when they came out, and honestly I hated it at first. I didn't like the physical design, nor the interface, and the huge loss of features compared to the 5G. But over time, I've grown to...kind of like it. I love the size, it'll fit anywhere you have a little space to spare. Mostly, I love the clip. Just leave it on my sleeve and forget about it, and when I need to change the song, it's right there.
But this new nano is very,
very tempting. Bringing back video playback is a big plus for me. I also love the new design, and the interface looks very nice (though I will have to try it out before I make a final call on that.) My only gripe would be the lack of a model larger than 16 GB. As is, my entire music collection will fit on it, but it doesn't leave a whole lot of room for video.
Also, I would miss the clip of the 6G
dearly. I could buy an armband or whatever for the new one, but it's so nice not having an extra case/band/whatever on my 6G to keep it hanging on my shirt.
I suppose I'll have to make a decision at some point. Lucky for me, I'm broke at the moment so I've got some time to make my choice.