The first preview version of SongBird, a XULRunner-based media player, has been released. Unfortunately, their site has been Dugg, so it may be a while before you can read all about it. The Digg comments have links to mirrors of the download itself, however.
A particularly interesting thing about this release is that, because they are combining Mozilla code with VLC code to provide the media playback functionality, they are using the XULRunner codebase under GPL terms. This is possible because of the ongoing effort to relicense the Mozilla codebase under a disjunction of three licences – the MPL, the LGPL and the GPL – thereby making the code available for use in many more projects. SongBird is the first in what will hopefully be a long line of innovations enabled by this change.
SongBird actually had to remove various bits of still-unrelicensed code to make their release, but they have managed it – which shows we are close. We are still hoping to get permission to relicence the code they had to remove – there has been movement on this very recently – but if not, it will be removed or rewritten, and then I’ll make a formal announcement that the process is finished.