After being a long time iPod owner, I'm switching to the new Zune with its subscription model. I haven't bought a Zune yet but I'm planning on doing so within the next month or so. 

I have approximately 40GB worth of music and my girlfriend has her iPod music library around 30GB. I've been trying to figure out how to migrate all our music off of our laptops/desktops and centralize everything on my NAS. 

In sharing iPod music isn't too bad. Sharing from one machine to all is fairly easy within the iTunes player. As far as storing all the music on a NAS, again, iPods aren't too bad and imagine other systems aren't difficult. But I'm really new to the Zune and I'm beginning to run into some issues.

My questions are:

1. Is it possible to store all music from our iPods and Zune subscriptions *and share music* between the iPod/Zune within the same file share on my NAS? I'm sure it's *possible* to store music on a share, but I'm not sure how iTunes and the Zune software differs.
2. Is there 3rd party software, maybe something like DoubleTwist that can sync based from NAS to multiple desktop/laptops? I've never used DoubleTwist but it's something that I found that looks *close* to being what I need. I've never quite done this myself so I'm trying to find a solution that can: a) store music on a network share; b) sync between different devices (Zune/iPod) *seamlessly*.