I don't think they really need to have an "Avengers"-style fight with punches and kicks.
Personally I liked how they handled the first meeting between the two in the animated series crossover. The two meet for the first time, and Superman, not really trusting Batman, uses his xray vision to see past his mask, revealing Batman as Bruce Wayne. Bruce realizes what he is doing and comments about him "peeking". Just a little bit later, if I remember correctly, Superman flies back to his apartment and gets in his Clark Kent clothes, only to notice somehow Batman had secretly put a tracker on his hero outfit. He looks out the window and sees Batman spying on him from a nearby rooftop.
It was more of a battle of wits more then a battle of fists, Superman flaunting his powers by just bypassing Batman's mask, and Batman flaunting his skill by using his knowledge and tech to figure out Superman's identity in turn. If they do anything, I hope they do that.
