"Once you perform the upgrade, your XP license is dead...."
Not really, unless "XP license" here implies a euphemism for "XP installation" since an in-place Vista upgrade installation is not reversible such that you can go back to the prior Windows installation - as was possible with earlier versions of Windows including XP, the impact of which is arguably negligible to the point that it is perhaps safe to say it's totally inconsequential.
For all intent & purposes you can still use the XP license for another system or partition installation & it would activate just fine - provided the license was legal from the get go.
"Yeah indeed your XP product key will be invalidated meaning you will have no choice except to buy a new key....."
Same applies here too.
"M$ is aware of it and hasn't yet bitten the MVP who revealed it to the world..."
M$ won't be doing none of that & neither do they have plans to disable the workaround at this time nor in the near future, this probably being because the act in all cases does not in itself constitute an illegal conduct & the fact that effluvium from the earlier WGA controversy is yet to clear the air - my assumption.
According to them, people WITHOUT (not with) a licensed copy of XP that use this workaround are violating the terms of use agreed to when they purchased the upgrade version of Windows Vista..........so, anyone that does this & already own a legal copy of XP isn't breaking any prohibited rule afterall.
http://www.vnunet.com/vnunet/news/2...
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