Nothing really outperforms an ipod, but I do very much like the zunes. I should restate: nothing outperforms, and few if any really underperform. The better brands are roughly equal in so many ways that only the little features and looks make much of a difference these days.
Those little flash zunes are great though. Zunes have podcast support now, and a great interface. I find the click/touch interface on the zunes to be much more intuitive than the ipod; I often feel the ipods are so user friendly that they're built for retarded monkeys. It's so simple it's actually too simple. with the zunes I don't have that feeling.
They also support the windows lossless encoder, so yet one more advantage of the ipods is mute.