Jaroslav Reznik wrote:
GStreamer backend facts:
* now default one in Fedora (F12, rawhide)
* GStreamer is Fedora's default multimedia framework
- better support from Fedora side? (PA, releases)
* Phonon backend not as mature as Xine one
- missing functionality
More bugs too.
* Maybe more support from upstream developers in the future? 
* Nokia is upstream
But nobody knows for how long because Nokia is working on an alternative
multimedia framework for Qt as part of the Qt Mobility project.