While this is not the first Harry Potter game to feature cast members from the film, as many seem to think (Goblet has Ralph Fiennes), the sheer number of people providing the voices of their characters here has risen quite substantially, to over 20 individuals.
In the game, Sirius' death scene is depicted more like it is the novel where Bellatrix hits him with unnamed but mostly harmless curse and it is falling through the Veil alone that kills him, rather than how it's seen in the movie where she uses the Killing Curse on him.
The first Harry Potter game to feature licensed music themes from the respective film franchise, coupled with certain cues returning from the first two games.
The first Harry Potter game not to include a voiceover narrator.
While this game does break away from the "from point A to B" gameplay of the previous title (Goblet), gamers still criticized the game for the path and camera remaining fixed throughout, restricting the free-roaming capabilities. This would be remedied in subsequent titles.