There have been many complaints about the Zune and how the WiFi sharing is crippled from a functionality standpoint, and nearly useless because there just aren't that many Zune around. I've been one of the people complaining, because I think there's potential for so much more. But even today, when two Zune users get together, some cool stuff can happen. A friend of mine here in Calgary has a Zune, and one night a couple of weeks ago we swapped some content. I beamed him a whole bunch of Zune-sized wallpaper images, along with some funny photos I've collected over the years. He swapped out his wallpaper a few times, looking at the images I sent, and several people in the room used his Zune and my Zune to look at the funny photos and we all had a good laugh. Without the ability to send images over wireless from one Zune to another none of this would have been possible. The Zune's screen size also made looking at the photos a great experience - though I once again curse at the fact that portrait-oriented photos aren't displayed in the proper orientation (this is a very bad decision on Microsoft's part).
On the music side of things, he beamed me over two full albums. I remembered to listen to them the next day, and I spent the next hour or so grooving to
Moses Mayes, a band I'd never heard of until then. The three plays limitation was enough for me to listen to the whole album three times, and by then I definitely knew I liked the band. I'm still not convinced that three days is a long enough - I don't listen to music on my Zune every day - but overall I'd say the scenario of sharing music is a very cool one that, once enough Zunes are out there, can make discovering new music easy and fun.
So, despite a rough start and some limitations, I'm a firm believer that wireless media players have great potential and sharing media with friends is a great social activity that the Zune makes possible.