I have an iPhone and a Zune HD. My iPhone is never used for music because the Zune is just an all around better media player. The interface is great, the OLED screen is amazing, and I subscribe to the Zune pass. The apps are really the thing tha sets the two apart.
My answer? If you just want the media player, get the Zune. If you have a fairly constant wifi connection and want apps, get the iPod.
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