Since AH is the only MMOG
AH is not a MMOG, first letter stands for Massively, and while we have the capacity for many, we are a small game by any standards.
To be honest with you.. I think it depends on the game itself and what the game developers allow the community to contribute.
AH is middle of the road on that scale. There are many games where you can be far more creative, the issue in AH stems for everything needing to be approved by the developers before use. Games in general tend to not care what the individual can see and only restrict what everyone is forced to see. Think of gun sights.. AH allows you the freedom to create any gunsight you want to use because YOU are the only person who gets to see it. Skins everyone can see what you have selected, so they are approved before being accepted.
In other games, entire texture packs, terrains, skins etc can all be player made and used immediately because they are on your end only and no one will see what you do.
Games like World of Warcraft have a lot of creative minds and players but they are left to making fan art, websites, etc.. since nothing player made is used in their game.
The film viewer of AH is unique, but the films produced are not.. almost all games out there have film makers recording game play and making masterful movies.
Our community is rife with talented individuals, film makers, photoshoppers, skinners, terrain makers, sound makers, gun sight makers, trainers, historians etc.. and it is the community in AH that sets AH apart, flight model means nothing if you are the only one in the sky.