gnonlin 1.2.1 is available: http://gstreamer.freedesktop.org/news/#2014-04-23T15:32:00Z
actually now it's 1.4.0: http://gstreamer.freedesktop.org/news/#2014-10-20T13:00:00Z
In progress
gnonlin-1.4.0-1.fc21,pitivi-0.94-1.fc21,python-gstreamer1-1.4.0-1.fc21,gst-editing-services-1.4.0-1.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/gnonlin-1.4.0-1.fc21,pitivi-0.94-1.fc21,python-gstreamer1-1.4.0-1.fc21,gst-editing-services-1.4.0-1.fc21
gnonlin-1.4.0-1.fc21, python-gstreamer1-1.4.0-1.fc21, gst-editing-services-1.4.0-1.fc21, pitivi-0.94-3.fc21 has been pushed to the Fedora 21 stable repository. If problems still persist, please make note of it in this bug report.