I just set up an XP system for my sister. The activation was painless. I'd prefer not to register, but then I've been known to fudge a bit on multiple installations, so I know why Microsoft (and Autodesk, and Sonic Foundry, and many others) have had it up to here with piracy.
If you have amonopoly on manufacturing hardware for your OS, you don't need to worry about piracy, but if Microsoft tried to control any aspect of manufacturing, they'd probably get a visit from the feds.
<];^)
Good points. Thanks.