MGibster
Legend
Well, that just gets back to the old chicken-and-egg question of whether D&D is so popular because its actively what everyone who plays it wants, or its popularity has made it the easiest game to find and thus the one people have gotten so used to. Its a question that's essentially impossible to answer in either direction.
I would humbly submit that D&D became so popular because it was a good game that provided players with a positive gaming experience. It continues to dominate because it continues to offer a positive gaming experience to many, many people. Being the biggest kid on the block has it's advantages, but if D&D wasn't giving people what they wanted they wouldn't continue to dominate.