Ubisoft tweets about issues with Watch Dogs authentication, saying "We are experiencing issues with the authentication services. Players may experience long delays when trying to login in-game. More to come." This was followed by word they were still working on it, and a post acknowledging the issue on their support site (thanks Ars Technica). The latest tweet on the subject seems to indicate things are clearing up: "The connection is rising and the issue still seems intermittent, the sign in system might work after several tries."