It seems to me that you are still requiring the software to report the proper CPU identification number. One thing that people are worried about is the ID number being given out to random pages for tracking purposes. Couldn't you build a page to ask for the ID numbers, then cashe those numbers in a file that can be downloaded and used by modified browsers and such to hand out while browsing the web?

Once you get a persons ID number, you would technically be that person to all the web pages you visited, and there would be virtually no way to track you down. Any server side software designed to defeat this would have to be made public, or even if it wasn't people would still get ahold of it, and cracked. It seems to me that a software program that can update the key and is specific to each users would be worth alot more security wise then a hard coded number that cannot be changed.

Oh yea, what happens when you sell the machine?