It was the first Batman movie that built upon the lore of the fims before it. Up until then all Batman movies were basically one-shots, having no connection to what came before. Talia al Ghul, Bane's connection to League of Shadows and even Scarecrow's inclusion were well done.
I have to believe that the Joker was meant to be part of this story as well. I would love to know what Nolan had planned for him in a fallen Gothem.