As mentioned before getting MXF support in GStreamer and Pitivi is a priority for us here at Collabora Multimedia. In that regard Sebastian is still working hard on providing GStreamer with top notch MXF support. The demuxer is mostly done these days, handling the testclips we have decoders for, so he is currently focusing on getting an initial muxer ready. He hopes to commit the first version of this muxer to gst-plugins-bad any day now, but while he cleans up the final bits of code, it would be great if people grabbed the generated MXF sample files and tried them with any MXF supporting application and/or library they might have around. If you are not able to load any of the files please let us know through our bugzilla and please include as many details as possible about your application and platform.
Another thing we are looking at the moment is getting some specifications written to put free codecs inside MXF, like Vorbis, Theora, FLAC and Dirac.