Laptops have the same problem. I remember one caught fire on a plane during flight. It is just a byproduct of needing high power from a small battery. If I remember right, Sony also had a problem with camcorder batteries. Something to do with the metal used inside the battery.
You would think the little I-pods would not require a great deal of power consumption, however...of course, with nano technology, it is most likely true.
I do not own the Nano, I actually own one of the smaller ones that was just released...but
does get a little hot sometimes...hmmm...
