Well I don't think fans would really mind if Assassin's Creed took a year off. The fact that a lot of them were not happy with the idea of Assassin's Creed 4 coming out so quickly was subdued because the game was good, but fear is rising that this franchise is turning into Call of Duty.
But lo behold, recent rumors suggest that Ubisoft might not be just coming out with one, but two Assassin's Creed installments for 2014. One of the games are supposedly being developed just for the PS3, Xbox 360 and Wii U while the other is being developed for the PS4 and Xbox One. In addition to that, the franchise is supposedly attempting a "massive re-scope" which could mean that they are going to change up how the entire story is going to head.
Considering that the open world gameplay of AC4 which got most of the credit while the story sticking to the usual formula got most of the flak, it seems that Ubisoft might indeed be thinking that change is due. In the middle they even had a survey asking if players wanted an open world sailing and exploration game, without the need to connect Assassin's Creed core story.
For now it seems that we might see some changes coming in the future, and this might be a way they hope to avoid the entire dilemma COD is facing right now. Other than that, it could just be that Ubisoft will be coming out with one game, but two different versions for current and next-gen consoles. Only time will tell what to really expect.