>This may not be helpful, and I am not an attorney. but there is no way to legally change
>an EULA once issued. IOW if you purchased the software under terms X,Y, and Z, it is not
>legally permissible for MS to change those terms to your detriment.

That is correct. However, every time you see a new EULA pop up with "Accept" and "Decline" options, they are renegotiating. If you click accept, you're bound to the new terms.