According to a press release issued from the producers of the game just less than an hour ago, it has been offically announced that the final HP game will be split into parts 1 & 2, like the movies on which they were based.
Although this may not be a surprise to some, considering that the
Harry Potter video games are greatly influenced by the films,
the fact that they would split the game into two games displays their
confidence that the game will sell well.
A trailer for the game and several hi-res photos were also released at the same time.