I don't get it...what's it supposed to do?
Essentially, that string of hex numbers is the "key" to decrypting the copyright protection on the next generation of media formats: Blu-Ray and HDDVD. The armor that was so painstakingly built into their technology, the shield that was designed to prevent you from ever watching it on anything but a Corporate-approved-and-licensed HDDVD/Blu-Ray player, the barrier put in place that would basically put the world in handcuffs in order to stop shoplifters ... turned out to be pretty weak.
It's important to bear in mind, before anyone even THINKS of siding with the corporate studios on this, that the level of copy-protection that they were trying to implement here was truly unprecedented. This goes beyond protecting a concept as abstract as "intellectual property," and stretches into the realm of never really being able to "own" any piece of media, anymore, no matter how much you pay. Indeed, one gets the impression that if some of the wealthier examples had their way, you'd never really have any legal rights to anything but the plastic the data was coded on.
Of course, in the technical sense, numerous laws and legal precedents state that one should be able to produce as many flippin' copies of anything they paid money for, whether it be to a hard drive, another disk, or anything else that could store it ... it's yours, and you can do what you like with it, aside from re-sell and/or assist in and out-and-out piracy.
In other words, the key that they're so desperate to hide (too late, now) pokes a hole in a wall that was standing on questionable legal ground to begin with. Deep pockets and ironclad connections prevented them from suffering much challenge on the issue.
I think they'll find the world of profane Internet 15-year-olds to be something quite unsubpoena-able, however. Mwah.