Ahhh.  I see what you're getting at.  What we should probably do, then, is disclaim anything from the Tech ARP source with something to the effect of "According to documents obtained and published by technology web site Tech ARP," ... like I said, there are a lot of tech news web sites that are repeating this, and the quality of the information shown in the Tech ARP documents is pretty consistent with how Microsoft goes about things, so I believe it should stay in.  That's what WP:V would have us do.  

As for the clean install part, well, Vista only supported direct upgrades from XP, not 2000, so it's not out of the realm of possibility that they'll only support direct-upgrading from Vista.  The Register contacted Microsoft on the topic of XP -> 7 upgrades, and they responded with ''“I can confirm that customers will be able to purchase upgrade media and an upgrade license to move from Windows XP to Windows 7 - however, they will need to do a clean installation of Windows 7, ..... This requires the user to back up their data, install Windows 7, re-install the programs and restore their data. For PCs running Windows Vista customers have the option of an in-place upgrade of Windows 7 keeping their data and programs intact or to perform a clean install of Windows 7.”  So.... that's that.  If Microsoft announces something different in the future, then we can amend the article.    -talk-