According to the last article, Microsoft is aware of the scheme and says it violates the Vista EULA."The type of person most likely to benefit from this workaround are power users and hobbyists who own multiple computers running Windows as well as Linux and Mac OS X. Indeed, one concrete scenario would be someone with a used PC that's just one or two years old running either Linux or OS X who decides to convert it to Vista and buys the upgrade version of the OS to do so.
"We are on the verge: Today our program proved Fermat's next-to-last theorem." -- Epigrams in Programming, ACM SIGPLAN Sept. 1982