Apple are recalling them due to a potential fault.
I hadn't used mine for years, and it was in terrible condition, with a broken screen.
I managed to find it at the bottom of a drawer and sent it off.
That was 5 weeks ago, and I had completely forgotten about it... So I had a nice surprise when an unmarked package showed up on my doorstep containing a 6th gen iPod nano. The small multitouch one, 8gb!
So if you still have your old iPod nano lying about somewhere it's definately worth doing!