Originally Posted by ChunkyB

Pretty much the same problem as with Windows. It's what most people are familiar with, and it's cheap. Most people don't want to make the effort to switch. The way I see it, it's like this:

Shimano = Windows: it's just what most people use. Not really by choice, but by default.
SRAM = Mac: It's different, and nice, but becoming more popular.
Campy = Linux: Users swear by it, and no one else can understand why.

Of course I'm a mac user, and I have only shimano stuff, so it's not a perfect analogy.