I'll be really interested to know if they've decided to overhaul the actual gameplay or if they just want it to be super polished.
For something like Assassin's Creed, I don't even know how six more months in the cooker would benefit the game. They've already got all the content, and no amount of work is going to improve stuff like the follow missions or assassination contracts - it's simply filler that isn't going to be fun no matter how you handle it. I guess they could put some work into improving free running, or the combat system, but even then it wouldn't be that beneficial.
My point being that when something with such a massive scope as Watch_Dogs reaches its current state, your hands are tied as to what you can feasibly change in order to improve the actual gameplay. You can buff up the graphics incrementally, but that's about it. Maybe a better multiplayer component?