Is it just me, or does it look like Sora is holding the Inverse Kingdom Key instead of his normal key? Is there any way someone could get a higher quality of just the image, or at least blow it up for a closer look? I can't tell cause the pic is so small, but if it is, this only strengthens my theory that I posted earlier.
I would say that Sora begins to use more of darkness while Riku uses the light. Since the trailer shows them both in similar situations in similar worlds, perhaps this game is going to be a bit of a changing of stature in the main character's standing? Perhaps Vanitas has something to do with Sora getting caught up in the darkness a bit more, and that will play into Sora getting into the realm of darkness to free Aqua?