Basically it's just a music subscription service. There are others out there, but this one appealed to me the most. It gives you unlimited download and streaming access to any music in the Zune Marketplaced that has been licensed for it. Frequently there are artists that don't have their music on there, but I come across those rarely enough. The argument against subscription services like this is that when you stop your subscription you lose all your music. Well, in addition to the unlimited access you get for $15/month, you also get 10 downloads per month to keep, free and clear. If you think that you would have bought at least an album a month anyway, you could think of the deal as getting the unlimited streaming for $5-6.

The major appeal of a Zune-capable phone to me is the possibility of wirelessly streaming my data to my phone wherever I am (with sufficient data coverage).