OK, here's why I think Zune just might work.
I mean... it's Microsoft. Someone mentioned that it's not everybody's favorite big corporation, but the big corporation thing is it's biggest asset. Most of the computers in the world run Microsoft Windows. What's to prevent Microsoft from seamlessly integrating Zune into the rest of the computer? Launch a hyperlink, and it goes to Microsoft IE. Launch a Media Player, and it goes to Windows Media Player. What's to prevent Microsoft from hawking the Zune at every one of these outlets? (Imagine the next generation IE that opens up directly to the Zune store. There's already something on Media Player that does something similar.)
Also, one of the most annoying aspects of iTunes is that .m4p format it uses for its music. .m4p files won't play in Media Player, which I use for most video applications and which I actually prefer over Apple's standard iTunes environment.
Notice this is a distinctly different situation from the Xbox (though, when you look at it, Xbox isn't doing so bad either). Xbox doesn't sync to a Windows computer. Zune does. And Microsoft can be pretty ruthless when it comes to trouncing rivals that run applications on their OS.
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Despite all this, I voted "No good."
Why?
The Zune is friggin' ugly.

I mean, seriously, Microsoft needs to hire some decent product designers.