Perhaps what we will see from this then is 2 flavors of Mac OS X. One that costs $1200 that you can install on any machine and get no support for, and one that costs $120 that you can install on Apple branded hardware.
That wouldn't work though, because the fundamental problem is that Apple isn't (or shouldn't be, anyway) allowed to impose that restriction after the sale because it infringes on the buyer's property rights and violates the Doctrine of First Sale and the Uniform Commercial Code.
In order to do what you describe, Apple should be required to present a contract on the outside of the $120 box and have the buyer (or rather, licensee since it's no longer a "sale") sign it, in ink, in the presence of an Apple employee, before handing over his money!
This is easy to get around. Every Mac can ship with a "$1080 off your next purchase of OS X" coupon.
I'm not advocating this, I'm just pointing out that it can be done in a way that does not violate any laws.