In January it was revealed that Toby Jones would return to voice the character of Dobby in Deathly Hallows however in a new interview he says he will be appearing in both the first and second movie. This would appear to imply that his character does not die until the last part of the story, giving further insight into where the narrative will be split.

Harry Potter 7 will open on November 19th 2010 and July 15th 2011.

Source: The Leaky Cauldron