Empire Magazine has a new article online where they discuss the Deathly Hallows split.

“We’ve played around with a couple of places,” said Heyman, “and ultimately settled on a place that we think is very exciting, and I think quite bold, in that it’s not necessarily where one might expect. You want to give a sense of completion, on one hand, but a sense that there’s another piece, more to come. We tried one and then Steve (Kloves, screenwriter) came up with the idea to try it another way and when we tried that, it felt just right.”

Daniel Radcliffe added that the split is “at a very tense cliffhanger”, which may be a bigger clue for fans.

I personally think they will end it when Ron comes back into the movie.  I hope I’m right, then I can brag 😉