AusGamers has interviewed Ubisoft Montreal's Eric Baillargeon about Watch Dogs, who talks openly about the PC version of the game, which he confirms will also support companion app functionality. They also go into detail on the notoriety system, side-quests, the tech driving the game and much more.
From the interview:
"Yeah, we aim to release in November 2013, on all current-gen and PC," Eric told us. "For next-gen platforms, the dates are still to be communicated, but yes it’s being built at the same time by the same team in Montreal, so expect it to have the same kind of delivery for every platform."