Now THIS is the way to have a hard drive behave.
Say you are in a business with critical or confidential information on your corporate desktops. A drive fails and you replace it. In the past, physical destruction of the bad drive was the only way you had to guarantee that the information on the platter(s) was unable to be recovered by a suitably determined person. But, should you have installed one of these drives, all you have to do is toss it. Anyone who wants the data on the drive has to have the encryption keys or they're stuck trying to break AES encryption which, as the article points out, is a whole 'nother kettle of fish.
Moving disk encryption to the hard drive using a small, inexpensive specialty microprocessor to handle the task probably makes it transparent to the user, or nearly so.
This is not the be-all and end-all of disk encryption, but it really is a good idea. I can't wait to read the technical specifics. I'll post them for you when they are released, later this week.