It should be considered retail, AFAIK, considering it came in a
nicely designed package, rather than a brown cardboard box which
OEM copies always come in.
I tried with a Vista Upgrade, double install worked fine. I'm
not too sure about 7 though, but since 7 is just Vista 2.0, it
should work too. You can buy the 7 upgrade, and if it doesn't work
as a clean install, you could download (NOT RECOMMENDED) Vista,
install Vista but not activate it, and then install 7 over it.
