I like the way how sometimes they just go right off course. Like Exorcism: The Possession of Gail Bowers is just a remake of the Exorcist, and nothing to do with Emily Rose, while Transmorphers is more Matrix sequel rip-off than anything else.
All science fiction movies are exactly the same these days. The "aliens are attacking AMERICA" motif is a little too calculated to bring flashbacks to the returning vets for my comfort.