But it's not. As Elvion said:
Basically thats the decryption key that was released (leaked) last night to HD-DVD allowing linux users to watch HD-DVD. Incidentally it can be used to copy/burn it as well.
The question was asked, is DRM worthwhile? My response:
I think DRM is tackling a real problem by the wrong method. Copyright protection is a genuine issue, but DRM is not the right solution. As I see it, the solution is to imitate another realm.
Look at photocopiers. When they first came in, the printing industry got really afraid. What happens now? Do people go to the library, borrow a book, photocopy it all, and return it? Not often. Why? Because it's against the law, and because it's so convenient to buy the book for yourself.
DRM is an attempt to prevent unauthorized use. It also makes legitimate use much harder. That is not a good thing. It needs to be really easy and convenient for someone to pay their money and listen to the song (or whatever it is they're wanting to do), and then people will do it. But get into an arms race against the pirates, and they'll win - because it's much harder for the manufacturers to uproot and change techniques. Freely distributed information will always beat the lockdown - eventually.
Anything involving embedded devices (eg DVD players) gets locked into whatever technology was considered stable at time of production. Suppose that includes some brilliant encryption technique, straight from the military. All DVDs could be encrypted, and all players have the decryption. That'd prevent other people from decoding the discs in some other system. But what happens in a couple of years, when that encryption algorithm is cracked? Do you recall all DVD players? Impossible. Do you release a new standard and try to expire the old? Also difficult.
Make it easy to do the right thing, and prosecute pirates in the civil courts. Build a culture in society that says it's OK to buy and not OK to steal. It works in other industries - shoplifting may add something to the price of your groceries, but it doesn't drive supermarkets out of business.