This is the first Pokemon film in which one of Ash's friends has a prominent role, in this case Max. The previous five movies featured Ash and/or a character-of-the-day as the central human character.
The lullaby that May hums was not dubbed over by American voice actress Veronica Taylor. It is that of Kaori, the voice actress that does May's voice in the Japanese version.
The prologue for this movie shows some of the main Legendary and Mythical Pokémon from the first five movies: Mewtwo, Lugia, Entei, Celebi, Latios, and Latias. However, Mew, the legendary birds, and Suicune were absent.
This is the first Pokemon movie in which a villainous team other than Team Rocket makes an appearance, in this case Team Magma.
This is the first Pokémon movie to not feature the season's theme song during the opening credits.