when playing back media on mac, make sure you are using a terminal associated with the currently logged in user!! using a different user will allow the video to show up

avbin is used by default in pyglet some discussion about the use of gstreamer in pyglet | http://code.google.com/p/pyglet/wiki/MediaOnLinux | http://www.mechanicalcat.net/richard/log/Python/Say_hello_to_pyglet

gstreamer interface reported to be complex.