I happened to run accross a file that gets created when you register your new Mac for the first time.
The name of the file is "Send Registration.Setup" and it is in the user/library/assistants directory
In the file in fairly plain text is your name , address, phone, all the stuff that they make you enter as you register. It also has an entry that reads your model from the ROM. (though not the serial number)
What's kind of humorous is at the bottom of the file there are two entrys,
<key> AppleSpam and <key> Othersspam
on my ibook since I checked no for both let Apple contact me for offers and for 3rd parties no as well both of the key values are no.
So Apple considers thier own marketing Spam?