You all seem to be jumping the gun here. Gwen standing on a bride staring longingly at the water does not necessarily mean that the Goblin will all of a sudden appear, take her up to the top and drop her. Her clothes look similar to the comics panel, sure, but I just don't think this is significant. And like someone said, for such an important and iconic scene, I highly doubt they would shoot it outdoors in broad daylight where anyone could snap pics.
Plus, why would any of you even want to see the "Death of Gwen Stacy" storyline play out in a movie that already has Electro as the main heavy, Rhino playing a part, and the introductions of Harry, MJ, and Norman? That's a lot of ground to cover in one film. I, for one, love the Green Goblin and don't want him to be sidelined just to squeeze in Gwen's death. I think Norman's fate (becoming GG) will be alluded to and built up throughout this film while the Spidey vs. Electro plays out and we'll get a full-on Goblin story (with Gwen's death) in the next film. It's just so much more logical. I think it's weird people can't see that.