The Mary Jane/Peter Parker romance was one my of my favorite parts of the first two movies. But 3rd one kind of killed it. I wouldn't mind seeing the character go.
Though what would they do? Say that they broke up for good and introduce a new love interest? Or just reference her as off screen. "Oh she is off performing in London" or something like that?
I know what happens in Spider-man 4 and 5! MJ gets kidnapped at the end of the next two Spider-man movies!