We've known for a while that Microsoft is offering a promotion to new PC buyers who upgrade to Windows 8 OS Pro, but the company has now said that it will be selling Windows 8 Pro upgrades online for $39.99. In stores, the price will be quite a bit higher: $69.99. The offer is eligible to anyone currently running Windows XP, Windows Vista, or Windows 7; it will last until January 31st, 2013. That's the same window offered for the current $14.99 upgrade deal
, but it applies to any current Windows users, not just those who purchase a new PC in the lead-up to Windows 8's launch. Microsoft says the offer will be available in 131 markets, and that it will release more details as we get closer to launch.