'Added Value' is infinitely better than any kind of authentication system. Piracy cannot be overcome no matter how much tech gadgetry one throws at it which leaves behaviourism. StarCraft2/Diablo3 will probably be the most pirated games in history and Blizzard knows it so they have expended a ton of work into the 'legitimate' experience by make BattleNet something that is desirable in its own right .. beyond merely acting as a match-making platform. With the mention of access to downloading mods from inside Civ5 I get the feeling that Firaxis are going to take the same route. If they make the tools extensive and interface enticing enough, actual piracy will be limited to the instant-gratification crowd, the ones that generate the used games in the first place.