With the updated iPod Touch, iTunes 8, addition of HD TV shows on iTunes and the return of NBC, the redesign of the Nano seems the most significant to me.

The previous design, 3rd generation, were quite ugly I think.  Just the design as well as the colors.  However, the updated Nano is simply stunning in color and shape.  The updated software, including Cover Flow, is quite impressive as well.  I can’t wait to play with one of these in person.