I’ve read all the Harry Potter books and seen all the movies, and for me the films have always been complementary to the books. They are part of the whole Harry Potter experience rather than standalone films.
The latest film is breaking a lot of records (despite a big drop off from opening weekend attendance), and that’s really not surprising, especially seeing an uptick in business from Deathly Hallows I to Part II because Part I is basically setup for this film. Part II is much more action-packed in addition to being the final part of the series.
Snape has always been my favorite character, and Deathly Hallows II showcases him to great advantage and reveals things about his character I suspected from the very beginning while showing a side of Dumbledore that others might not have guessed or wanted to believe.
But, there’s more to the success of the films than the fact that my favorite character gets a lot of screen time. The adult characters in the films have always been played by great actors, and the young leads have developed as performers as the series unfolded.
Also, another key to the success of the films, and the books for that matter, is that the plotlines have become more complex and the character development more mature as the young leads have grown older.
Even though this is one of my two favorite films in the series, I have always seen the films as fun diversions and reminders of how much I enjoy reading the books.