If you're hoping to get in on discounted pre-order pricing for Windows 7 in the UK then you'd best get to clicking, son. We're hearing that copies of the £50 Windows 7 Home Premium E are already sold-out on Amazon but still available at Play.com, for example. Stocks of Windows 7 Professional E look plentiful at £100, for the time being anyway. While the offer is scheduled to go until August 9th, it's limited to some magical quantity known only to Microsoft and its retailers. If you're still on the fence remember, Japan completely sold-out in just a few days.