Marc Web explains to Crave Online his reasons for removing her from the sequel:
CraveOnline: MJ got cut out of Amazing Spider-Man 2, we heard this. How tough a call was that?
Marc Webb: It wasn't… The character was just teased. It was a very minor inflection and I felt it was important to really focus on Peter and Gwen's storyline. It was hard because I love Shai. I think she's such a brilliant actor and such a lovely, wonderful warm person. That was hard and having her presence in a movie is great but I thought it was important to focus on Peter and Gwen. I'm excited to see Spectacular Now, though.
So, there's no chance of like, a post-credits thing where he just opens the door, "Face it, Tiger, you hit the jackpot?"
Not in this one. Well, maybe. I don't wanna give the plot away.The film hits theaters on 02 May 2014.