If you’ve been wondering how the Zune’s user interface will compare with the iPod’s, we have 
some real answers for you this morning: the similarities are significant, but Microsoft has made a number of changes that range from cool to not so cool.
That Wheel Thing: Not so cool. Turns out that there’s no touch-sensitive scrolling feature here - it’s shaped like a wheel, but it’s really just buttons. Zune has a menu button on the left of the circle, scroll buttons within the circle, and a play/pause button to the right of the circle. There’s also a hold switch just like Apple’s on the unit’s top, near the headphone port. You press up and down on the “Wheel” to scroll up and down through menus. Zune interface, features detailed | iLounge