It took just four days for Windows 8 to hit four million machines (ours included), and in just over a month, Microsoft has managed to sell some 40 million licenses of its tiled OS. To date, Windows 8 is outpacing Windows 7 in terms of upgrades, but given that the company had moved 600 million copies of the latter back in June, the new kid on the software block still has quite a ways to go. The news comes just hours after Microsoft also announced that it had sold a whopping750,000 Xbox 360 consoles during the Black Friday weekend, which makes the omission of one other number that much more glaring — after all, if it’s so easy to dig up Xbox and Windows 8 numbers, why are we left with awkward adjectives todescribe Surface sales?