Earlier this evening many players reported that they were experiencing an issue with the Spinning Revolver which was preventing them from loading the game. We apologize for any inconvenience or interruption that this has caused to your game-play.
This was in relation to updates that were released today, and the development team has been made aware of this matter. They have pushed a fix that has resolved the issue for most players.
In order for the issue to resolve please clear the cache for each browser that you use to access the game. Instructions on how to complete this action can be found through the following link.
While the issue was being experienced we advised players to access the game via www.mafiawars.com, which provided a resolution to the loading issue for most players. If you continue to experience the spinning revolver, please try accessing the game through that link.
Please allow some time for the fix to populate across the platform for all of our players. Should this issue continue to persist after several hours, please email us through the following link.
Again, we apologize for any inconvenience and want you to know that the issue has been addressed, and we appreciate your patience during this process!
Info from Zynga Customer Support