Today we nailed down a policy for Xiph on what file extensions and mime types we recommend using for Xiph technology.
Basically, we have introduced some new file extensions to allow applications to more easily identify whether they are dealing with audio (.oga) or video (.ogv) files, or some random multiplexed codecs inside Ogg (.ogx).
We recognized the fact that existing Ogg Vorbis hardware players will need to continue to work with whatever scheme we come up and therefore decided to dedicate the extension .ogg to Ogg Vorbis I files – and deprecate all other use of it. That includes the deprecation of the use of Ogg Theora and Ogg Flac with this extension. In future, Ogg Theora files should have a .ogv extension and Ogg Flac a .oga extension. (For further details, check out the wiki page.)
MIME types will be changed accordingly and the RFCs required to register them will start to be authored now.
None of this has been written in stone yet though and there is still time to change this policy if it doesn’t make sense. So if you have any strong objections, speak up now!