"Of course, the advantage to that happening would be that it would put DRM front and center to Joe Public. Right now, most people don't "get it". Disable their hi-def player and force them to buy a new one"

Joe Public wouldn't have to buy a new player...they would have to connect it to Sony (via a network connection) and get new keys. That being said, the initial result would be enough to piss off a customer. Regardless, that's how the technology is supposed to work.

"So far, Sony has tried to introduce new copy protection mechanisms that have only really affected people that want to make copies of their movies. They have yet to seriously cripple any hardware."

Incorrect. The root kit automatically installed itself onto any computer the CD was played on, whether or not someone was trying to make a copy. Not only were many computer OSes damaged, but when Sony sent a "fix" designed to remove the rootkit, it only made things worse. There was a lawsuit for folks whose computers were disabled, but it only came out to about $70 a person.

[EDIT]

Here's a good description:

A good analogy is with a physical lock and key. With DVDs, someone figured out how to make a universal key that opened every lock. With AACS, keys have been stolen, but the AACS lock can effectively be ‘re-keyed’ so that new keys are needed, making the older keys useless.

While the AACS keys had originally been stolen from HD DVD discs, it didn’t take too long before similar keys on Blu-ray discs had also been stolen, resulting in the release of two software programs – BackupHDDVD and BackupBluray.

The AACS copy protection body is supposed to be able to issue new keys on future HD DVD and Blu-ray movies that invalidate the stolen ones, but questions remain as to how successful this will actually be. Could it not work as intended on early generation HD DVD and Blu-ray players, causing playability problems with movies in the future?

I know, for example, that the latest Pirates of the Carribean BD had a newer key, because an older key had been made public. Ironically, the new key for the POTC BD had been made public before the DB had been released, rendering the new protection moot.