Comment 3 for bug 272121

The base UNR builds cannot include codec packs like gstreamer0.10-fluendo-plugins-mp3 -aac, etc because it is not legal. OEM's shipping UNR have to pay license fees for these codecs and then they can be included in the OEM specific build.

So this means out of the box base UNR will not be able to play the most popular audio/video types without user interaction.

This is the path users have to take if the "licensed" codecs are not installed and they want to play a movie.
1)click on movie in browser
2) totem plugin in Firefox basically does nothing and shows a movie icon
3)right click on movie icon in Totem and select "Open with movie player"
4)Movie player will ask to search for suitable codecs, say yes
5)select all the gstreamer plugins that it says you need and install them
6)movie should start playing in Movie Player
7)refresh browser and movie will start play in browser

would be nice if totem plugin prompted you to install the appropriate codecs, but it currently does not