Looks like the article was edited. It now says:
From June 26 to July 11, while supplies last Microsoft will offer special preorder pricing. It will be offering in the U.S. Windows 7 Home Premium for $49.99 and Windows 7 Professional for $99.99, a savings of $70 and $100 respectively (In the U.S. preorders are for upgrade versions). Canada and Japan enjoy similar deals.
Still is pretty awesome. This motivates me to preorder it, though I was planning on upgrading regardless. My desktop runs XP, but on an ancient 50GB hard drive. I'm going to get a new hard drive and just do a clean install.
Unfortunately, if I do that, I think I'll need the full versions of Windows 7, not the upgrade versions...
Windows 7 requires user to format if they're upgrading from XP, but i think you can still use the upgrade DISKS for it.
also: kinda sucks it wasnt really the full retail versions for that price
Edit: if i were you, i'd get your new hard drive, and ghost it using
Clonezilla, so that you have your current install, and can use the upgrade disk on your new hard drive.