From the article: But what about Mark Cuban's copyright argument? Why isn't YouTube is trouble in the same way Napster and Grokster were? The first difference, as indicated, is that Napster simply wasn't covered by the 512 safe-harbor law, and YouTube is. Napster wasn't "hosting" information at the direction of its users, but rather providing a tool for users to find and download predominantly infringing content. It may sound odd that Napster gets in more trouble for helping you find illegal stuff than YouTube does for actually hosting it. But that's the law and why YouTube should really, really thank its friends at Bell."