Oem is basically retail, they changed the license agreement.
They wanted to reduce the number of versions and so make it easier.
Can you use the same copy on a new PC like the old retail or is it tied to one machine?
Nope, not tied anymore.
It's transferable like retail was.
looking at it again yes I did misread itWhere does it say that? I'm positive you're wrong
It apple as to upgrade versio not just PUL verison. You can. Even. Give. Upgrade to someon else, if you uninstall it.
The upgrade is independent of the underlying OS. You just need
A) a valid underlying license
b) only have one I stance of it installed.
I think legally noOut of interest, can you still run a system with Windows 7 seperately after using the Windows 8 upgrade?