MSN Music supports RSS

Microsoft’s new music service supports RSS feeds with top 100 songs, albums and artists. The feed also contains a link to a 30 sec clip of the song. It defines a tag called "enclosure" for inserting the link to the song within RSS.

<enclosure url="mms://a992.v11451c.c11451.g.vm.akamaistream.net/7/992/11451/v0001/msnent.download.akamai.com/12336/BFHJ23HZ/Prod/wma/v9/Audio/07/75/55/557507.wma?WMCache=1&WMBitrate=200000&WMThinning=1&ibcd1=songid11493990" type="audio/wma" />

But one needs to use IE and the song can be played in MSN Media Player.

Thanks to Danny Ayers for the link.