ADDED: Some analysis by a lawprof, Stuart P. Green:
The problem is that most people simply don’t buy the claim that illegally downloading a song or video from the Internet really is like stealing a car. According to a range of empirical studies, including one conducted by me and my social psychologist collaborator, Matthew Kugler, lay observers draw a sharp moral distinction between file sharing and genuine theft, even when the value of the property is the same....That is, let's be realistic and honest about what we really think is morally wrong in this area and adapt the law to that. Obviously, our ideas about morality and intellectual property have shifted with the changing technology and — let's face it — our desire to justify what we've done and what we want to do. We're talking about statutory law, and this is a democracy, so we can have what we want. We just need to think rationally and long-term about what will give us what we want.
[W]e should recognize that the criminal law is least effective — and least legitimate — when it is at odds with widely held moral intuitions.
... People who work hard to produce creative works are entitled to enjoy legal protection to reap the benefits of their labors. And if others want to enjoy those creative works, it’s reasonable to make them pay for the privilege. But framing illegal downloading as a form of stealing doesn’t, and probably never will, work. We would do better to consider a range of legal concepts that fit the problem more appropriately: concepts like unauthorized use, trespass, conversion and misappropriation.
Here's Stuart P. Green's book, upon which the linked op-ed is based — "Thirteen Ways to Steal a Bicycle: Theft Law in the Information Age."