I think he may be referring to a proposed one-time-rule during Vista beta 1.
It actually appeared in the EULA that accompanied the early builds. The
techbeta folks spotted it right away and raised holy hell because techbeta
testers happen to also be the kind of technology entusiasts who like to keep
up with hardware advances and so tend to move their copies of Windows
several times. The outcry was such that MS relented and dropped making
retail Vista a one-time-transfer license. You have more things to thank the
techbeta testers for than just bug swatting.
It was long gone by the time beta 2 released for public trial through the
CPP in mid-2006. Unfortunately it was blogged during beta 1 (should not
have been) by some techbeta folks and so reached the general public. The
one hangover from all of that was in the Anytime Upgrade license but MS
finally had to give that up too. So he was right and he was wrong. It was
changed before, not after, Vista released.