When someone other than the two players involved a game replays that game, I suggest those players be sent an automated offline message (received when they log on) that notifies them of who watched their game, and which game it was.
 
Although I voted “No” in the poll regarding whether all games should be publicly viewable, if this suggestion is implemented then I would definitely support all games being PV, since everybody will have warning of any player who is potentially scouting their set-ups.