Well, since, obviously, I haven't seen the movie yet (haha) it's hard to know what they intend. I don't think it would work for them to put romance between the two in there, even if they wanted to. Why? Because if they intend on making the Voyage of the Dawn Treader, that would mess up Caspian's story. He is suppose to marry that man's daughter (I can't recall his name at this moment, but I'm sure most of you know what I am talking about). And if Andrew was so careful to make sure that LWW wasn't messed up, and kept it's true message, I would be surprised for sure if he decided to put something like romance between susan and caspian. All that can be said right now is....well...we will find out next year, now won't we? haha