It would be nice to have special field for saving caption of embedded video. For now youtube supports retrieving it.
I believe we're storing it in the data field, but it's not being used yet. Should probably create a new formatter for it. Moving to the Media: YouTube queue for now.
There are FCC rules coming out for soon that will hasten our need for this feature as well, so we may be able to spare some cycles to help out in this regard
This could be related to this issue if someone wants to do a backporthttp://drupal.org/node/1990660#comment-7396208
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