Book 7 to be split into two movies?

I have nothing against the book being adapted into two 'semesters' as I assume they would be called. However, it seems such a delayed move. Columbus, the director of the first two movies, set a high standard but had the advantage of adapting the shortest books in the series. I am reluctant to see the films after Cuarón adapted "The Prisoner of Azkaban." The third book was *longer* than its prequels, but the third movie was the shortest of the series at the time of its release. Much to my personal resentment, elements of the Marauders' Map were left out; Harry never learned in the movie that his father, Lupin, and Sirius made the map, although the fact that Harry himself chased Pettigrew was, in my opinion, an improvement on the source material. The artistic choices were beautiful, but I had nevertheless expected a closer adaptation, and a longer film, in keeping with the Columbus films. But the fourth movie was very well adapted considering how much of the book had to be adjusted for length. So back to topic, I was almost certain the "The Goblet of Fire" would be divided like the "Matrix" sequels and the "Lord of the Rings" had been done. If the studio saw no reason to slice "The Order of the Phoenix," then I can see no legitimate argument to cut up the seventh book, which is shorter. If they had cut up the fourth, fifth, and sixth, as I feel they should have anyway, we wouldn't be having this discussion at all. I could also, however, imagine that Rowling may yet add material solely for the seventh film, in regards to elements she is writing for her character encyclopedia or eighth book. I can definitely see an expanded epilogue in the cinematic adaptation, but I don't think that alone could warrant a double feature.