Earlier today Tim O'Reilly wrote an excellent article on how Wikipedia is the new face of publishing. Fundamentally, he writes, Wikipedia is much like any other publishing organization because it has both "a large network of contributors and a core of committed regulars". That is why it puzzles him when publishing houses scoff at Wikipedia's content generation model. After all, they use the same model themselves.
This is just as true of any publishing company. Did Bloomsbury's editors invent Harry Potter? No, it was a welfare mom who dreamed up the idea while riding on the train.
What has changed, though, is the technology that brings contributors and publishers together and the speed at which all this happens.