Today's the big coming out party for Assassin's Creed IV: Black Flag. While we already knew the PlayStation 3 version was going to have this, we can now also confirm that the PlayStation 4 version of Black Flag will include 60 minutes of additional gameplay as well. It'll be made available to either platform through the PlayStation Network sometime after launch on October 29.
Assassin's Creed III also had exclusive story content during the initial release. If Ubisoft follows the same pattern, then whatever this exclusive content is will be released to other platforms once some kind of "Complete Edition" is revealed that will include the full game and all the downloadable content, like the Washington Edition Europe is getting.