I pulled this off of IGN for you:
'Crews', which have been seen recently seen in Max Payne 3, will also be used in Grand Theft Auto V. The 'Crew' mechanic makes use of Rockstar's Social Club, which has been in use since the release of Red Dead Redemption. By creating a 'Crew' in a game such as Max Payne 3, players will be able to port across their character between the two games.
Rockstar boss Dan Houser said: "Multiplayer is an ever-more important part of all our games moving forward. By creating crews through Social Club, the crews that you create in Max Payne 3 will be ready and available for you to play in Grand Theft Auto V from day one."
GTA V will let players form private crews with friends, or join public crews. Players can be a member of up to five at the same time, and completing tasks as a crew will gain experience points for the player. In late 2012, Rockstar said that "refining open-world multiplayer into something really special" had been a huge focus in the development of GTA V.
Based off looking at my profile alone it looks like you can have multiple crews.