The question of copyright violations in article histories has come up before. See
about halfway down
http://meta.wikipedia.org/wiki/Wikipedia_and_copyright_issues.
Isis suggested that we keep copyvios in page history, because:
# The page history is an editing tool, not something we "publish"
# It would be good evidence of our procedure in any court case
Is there a list somewhere of legal questions that wikimedia should (eventually) get a
paid legal opinion on?
-Martin "MyRedDice" Harper