Today Ubisoft officially confirmed that they are working on Assassin's Creed 4. The name is going to be Assassin's Creed 4: Black Flag and it will be released for PC, Wii U, Playstation 3 and Xbox 360. The Playstation 3 version will have 60 minutes of extra gameplay, compared to the other consoles.
More information about Assassin's Creed 4 will be givin on the 4th of March. So far we can only speculate about the storymode. Looking at images Ubisoft has published, we see a ship in the background with a black pirate flag. This might indicate that the story contains pirate as was previously rumored. Some rumors also state that you will play with the father of the main character in Assassin's Creed 3, Connor.