I released a JavaScript library with Silverlight application for playing the Windows Media files on the Firefox. It’s named “Lyra”.
You can download it and see more detail below:
http://api.x-jukebox.com/lyra/
And Lyra is open source and is freely distributable under the terms of an BSD license.The repository is open in my project site: http://projects.makotokw.com/trac/arcadia/browser/lyra/trunk
The Lyra has some limitations, current version is alpha version. At the first, I will use to the Lyra for mRadio is supported on the Firefox. The mRadio (http://x-jukebox.com/mradio) plays 200 sample contents (.asx file) of Mora seamlessly. ( “Mora” is Japanese Music Store look likes iTunes Music Store)
Please let me know if you have any questions!