The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Most Wanted Entertainment (Developer) (2 members)
- MotoGP (Series) (6 members)
- MotorStorm (Series) (4 members)
- Move Street Cricket (Series) (2 members)
- Move handler: Fake (Config) (1 member)
- Move handler: Mouse (Config) (3 members)
- Moving Player (Publisher) (2 members)
- Mugen Souls (Series) (2 members)
- Multi-platform (Release type) (1,165 members)
- Multiplayer (Game mode) (814 members)
- Multithreaded RSX: Off (Config) (2 members)
- Multithreaded RSX: On (Config) (24 members)
- Music (Genre) (83 members)
- Mutated Software (Developer) (1 member)
- Mutated Software (Publisher) (1 member)
- Muv-Luv (Series) (5 members)
- Mycom (Publisher) (1 member)
- Mynavi (Developer) (3 members)
- Mynavi (Publisher) (2 members)
- N-Space (Developer) (1 member)