According to a Ubisoft community manager on the publisher's official forum, Far Cry 3 will not have a dedicated online server.
In a post by Ubisoft community manager, Far Cry 3's "online experience does not support dedicated servers". Responding to claims the move will "kill the PC community", the same spokesperson had the following to say:
"Of course we are not trying to kill the PC community. We have simply decided on a different way of handling multiplayer. We weighed the different options against each other to see what worked best, and what we came up with worked very well even without DS's [dedicated servers]."
Ubisoft released a new gameplay video earlier this week that showcases the fire and wildlife in Far Cry 3, which releases November 30.