Could a major plot element be responsible for Mary Jane getting axed from Spidey 2?
We already know that, despite having filmed scenes for Amazing Spider-Man 2, actress Shailene Woodley had been cut from the film, even though she was cast as Mary Jane Watson. We've also heard that it's almost definite that Mary Jane will now have to be recast. That's a lot of money and time wasted, not to mention bad PR.
So there would have to be a very good reason to make this change. The latest rumor we've heard is about as good a reason as you can get. According to Hollywood Life:
Emma Stone’s character dies in the next film and that really would take a bunch out of the film if Spider-Man all the sudden starts dating a new girl so close to an important characters death. They were noticing this occurring as they filmed Shailene’s scenes. They want to make the death of Gwen Stacy really mean something and then it will leave room for Shailene to shine in the third film.
So rumors that Emma Stone was mad about being upstaged are, apparently, false, as are any niggling doubts that negative fan reaction to Woodley played a part in this move. In fact, Gwen will apparently still appear in subsequent films.
There is no jealousy, this is definitely a creative decision, and Emma was also told that she would have her character get the proper sendoff and probably would appear in flashbacks and nightmares in the third film. When you are a huge star like Emma you get things thrown to you even if you don’t ask or demand them.
While these rumors are unconfirmed (for obvious reasons), they do make a lot of sense. Gwen's death is inevitable, and having MJ show up before that even happens feels like a bit of a narrative misfire.
(via Comic Book Movie)