Below is a excerpt from the MTV interview there are 3 below and more on MTV site link at the bottom
Going for the Gold: In "Twilight," RPattz and the rest of his vegetarian vampire cohorts have gold-colored eyes as a result of abstaining from consuming human blood. For "New Moon," the vamps' eyes were clearly more golden. Why'd Weitz have his actors switch to brighter contact lenses?
"It's a more noticeable gold," Weitz said. "I thought that in the first film they hadn't popped quite enough and I wanted to have that sense of otherworldliness carry through more."
The Silent Vampire: Actress Rachelle Lefevre was notoriously replaced in her role as the vampire Victoria following "New Moon," with Bryce Dallas Howard taking over the part for "Eclipse." In "New Moon," Lefevre is seen but does not speak. Is there a connection between her lack of lines and what happened with the casting decision?
"It wasn't so much that," Weitz said. "There was a dialogue scene with her, and eventually that will show up whenever they release deleted scenes. It was one of those scenes that, when you look back at it, it's kind of a surplus to the whole storytelling requirement of the movie. So there was no ill intent there. I wrote Rachelle and explained why that scene didn't end up in the film, and in terms of filmmaking I can't regret it, although I do regret it very much if it hurt Rachelle's feelings."
Black Eyes: In Stephenie Meyer's book, Edward's eyes go black in Italy. Why don't his eyes turn in the film?
"It's because I screwed up!" Weitz admitted.
Really? He just forgot?
"Well, yeah, I kinda did," he said. "Well, there are two reasons. One is that I messed up. The other reason is that I actually thought that onscreen it would be quite bizarre to see his eyes go completely black, and that it would be more satisfying and less jarring to have that moment of reunion be a reunion with revivified Edward. But probably, the long and the short of it, there are many details that I did not drop the ball on, and there are some that I did."