As if Amazon wasn't doing well enough with Windows 8 sales, seeing pre-orders dominate it's Best Sellers list, they have decided to sweeten the deal. Now you can pre-order Windows 8 Pro for $69.99 and get a $30 Amazon credit to boot. For those of you who aren't too good at subtraction, that brings the price down to $39.99, the same cost as the online upgrade price for current users of previous Windows versions.
The promotion with the $30 credit also applies to Windows 8 Pro Pack, which will let you upgrade from Windows 8 to Windows 8 Pro. So if you are thinking of building a new PC or upgrading the one you've got, you can find both deals in the source links below.