American University's Center for Social Media has released Recut, Reframe, Recycle: Quoting Copyrighted Material in User-Generated Video, which examines fair use issues in user-created digital videos. See the announcement for links to videos used in the report.
Here's an excerpt from the "Next Steps" section:
The effervescence of this moment at the dawn of participatory media should not be mistaken for triviality. The practices of today’s online creators are harbingers of a far more interactive media era. Today’s makers—feckless, impudent, brash, and extravagant as they often are—in fact are the pioneers of an emerging media economy and society. Recognition of the importance of fair use, within the copyright law toolkit for cultural creation, is both prudent and forward-looking for those concerned with maintaining an open society.