FilmSchoolReject has an interesting interview with New Moon screenwriter Melissa Rosenberg where she talks about how she handled the blank pages of New Moon:
Beyond the usual difficulties adapting something, this is the book that involves blank pages to show emotion. How do you adapt empty pages for the screen?
What I did was to show the passage of time and the lack of movement for [Bella]. That was to put her – have you seen the movie?
I haven’t gotten a chance yet. They screen it Wednesday.
Ah. Well, so, I put her – there’s a scene in which that passage of time happens, and it’s her sitting stone-still as time and seasons pass around her, and Chris [Weitz] did some really beautiful stuff visually with that. So that was my way of putting that same sense of blankness, and yet, the time is passing.
Check out the rest of the interview where she also talks about Eclipse and Breaking Dawn here.