Ashley Greene States That She Wouldnt Mind The Breaking Dawn In TWO Parts 

i dont want anything missed, out .
i want to see everything. i dont care if i have to send all my money on two parts. i want to see everytthing come to live.

"The book is huge, but the inner stories give NOTHING to the overall plot."

Aye! Aye, Captain! *spongebob voice*

There isn't actually much to cover on really.

Wedding->Honeymoon->Pregancy->Wo­lf pack drama->Birth of Renesmee (the demon spawn)/Imprinting->Bella's transformation(POV)->"The Volturi iz COMING!'->The vampire gathering->The war that never came->And they lived happily ever after... the end (Throws sparkles and unicorn-shaped confetti)

There's more talking/chitchat in the book than the drama... I'm sure they can just fit it into one movie.

^Agreed