It's also pretty easy to create a large scale business by taking shortcuts like streaming copyrighted content. Look at Grooveshark, Stage6, or any of the hundreds of popular torrent sites.

For someone who's used to creating normal web products it's shocking to see how fast a site can grow with copyrighted content.

It's not "make something people want" it's "give people what you already know they want but can't get for free".