Watch Dogs multiplayer will have an eight player free roam, as confirmed by the Creative Director of the game, Jonathon Morin.
Jonathan Morin responded to fan speculation that Watch Dogs multiplayer will consist of an eight player free roam in an open world. The full extent of this multiplayer mode is not truly known yet, but it is reasonable to believe that we will learn more at GDC 2014, as the game is launching in just two months time.
There are also rumours that PS4 version will run at 1080p/30fps whilst the Xbox One version will run at 960p/30fps, with the PC version being able to run at up to a 4k resolution with a variable frame rate. However, there are no confirmations from Ubisoft as to whether this is true yet, so it is fair to say that until an official comment is made, these assumptions are likely to be false.