I cant believe nobody posted this yet! its so obvious!!!!!!

In the scene where Rose meets Jack on the bow and she "flies", look behind her at the set when she says "They told me you'd be up here" or something like that. The scene is so obviously fake. You can see actors walking in front of it, but it doesn't help make it look more real.

For a movie of this caliber, you'd think they could spend the money for just ONE more set to avoid stuff like this