While Apple has sold millions of iPods, their real value to Apple is how tightly intertwined the devices are with the iTunes music service and iTunes software. If you own an iPod and want to download music, you must use iTunes, which has sold more than a billion tracks in its relatively short life.

The Zune, which was released Tuesday, isn't yet a compelling enough device to pull many customers away from the iPod. But if you look at Zune in combination with the Zune Marketplace online store and the software that connects the device with the store, Microsoft's effort is more compelling. It's still a work in progress, but in a few ways it already equals and even surpasses the iPod/iTunes juggernaut.

Beautiful interface

Zune is, overall, a competent 30GB player that is particularly attractive in some areas, misses the target in others and strikes out entirely with one of its most visible features.

To start with the positive, Microsoft succeeded at something no other media player vendor has: It has created a graphical user interface that is, subjectively, as compelling as the iPod's. To do that, Microsoft took a minimalist approach, offering relatively few options but giving users fast, easy and eye-catching access to media.