Some snippets from The Register's response to Orig's article:
http://www.theregister.co.uk/content/4/26301.html
MS planning to tackle leaked WinXP keys with SP1?
By John Lettice
"The procedure BetaONE envisages (and it's about the only one we can see would have an effect) is that all corporate customers will be issued with new keys that are recognised by the new code in SP1. So if that's correct, all current corporate keys are dead, the luckless corporate techies will likely get somewhat irritated about having to reactivate, but hey, activation with a corporate key is supposed to be trivially easy, right?
The new key generation system may be more difficult to get round than the last one; indeed, if it isn't, there isn't a lot of point in Microsoft implementing it. That, however, is not the problem. Microsoft's difficulties arise not from people actually cracking the key system but from corporate keys leaking, so no matter how good the system, if a key is leakable, it gets circumvented.
...Inexorably, one is drawn to phoning home as the real shoe two. The EULAs are being amended so that Microsoft reserves the right to check the validity of machines' licences, which means the company will be able to check online for leaked keys, and take what it deems appropriate action. Checking via Windows Update would allow the identification of corporate keys that had leaked out of the corporate market, and this could be followed up with the owner of the key...."