Comment 477 for bug 412647

Yes, but the only pratical point of adding gstreamer is adding support for H.264, since all the free formats are already natively supported (while other formats aren't interesting in firefox). Other softwares need gstreamer because is the only supported backend also for the free formats.

Also, while flash is widely used, HTML5 video still is not, and there is still not a winner between H.264/Webm, so there is a point in supporting only free formats here - at least until/if H.264 definitively wins over Webm.