There is an update to these components which allow you to play Windows Media files in QuickTime on your Apple Mac OS X system:

With Windows Media® for QuickTime, by Flip4Mac™, you can play Windows Media files (.wma and .wmv) directly in QuickTime Player and view Windows Media content on the Internet using a Web browser.

Windows Media® Components for QuickTime has been highly optimized for Power Mac G4 and G5 and Intel computers and supports playback of high-definition Windows Media video files.

Windows Media playback is provided for free. By upgrading, you can import Windows Media files for editing and create Windows Media files for distribution. To learn more about these advanced features, visit the Flip4Mac Web site.

So I know there are a few Apple users who lurk on this site – go ahead and grab your download :-)

Download Windows Media Components for QuickTime