New
#11
NO, if you purchase a retail license (as you've proposed), you are free to use that license on only one machine at a time, regardless of how you may change or upgrade that ONE machine or whether you uninstall from one machine and install it on another. You're talking about buying a retial single use license - single means single. It's more flexible and valuable than a manufacturer's installed OEM license which is only good for the life of that one machine the manufacturer assembled and installed an OEM license on as part of the assembly.
EDIT - my answer was a little longwinded, hence Brink's summary answer beat me to it.
Thanks for clearing this up for me guys.
I've got one laptop upgraded successfully. However the licensing agreement doesn't work for me so unfortunately for MS I will be hanging on to my money this time around.
Insane or not, its the way it works. If you bought 2 laptops brand new, you would be paying for the OS license twice. If you own and drive 2 cars, you need 2 license plates and 2 registrations.
Consider running a different OS on your 2nd computer. It's a great opportunity to learn something new. Maybe paying for Windows a 2nd time would seem more reasonable if you didn't enjoy the free options.