Got Xbox Live? Like Free games? Like the The Witcher 2: Assassins of Kings? Well what the heck are you waiting for dude? Jump on the Xbox Games store and download it, the game is actually is free via the right now and nobody seems to know why?
This would appear to be some sort of glitch and we do not think that the game should be free, it hasn't been announced anywhere that this AAA title would be free.
Before you go getting too excited, this game is only available in certain regions and wouldn't you know it, the UK isn't one of them! Xbox Games Store for some reason, so you should probably snap it up while you can. However, it's worth noting that the offer only seems to be available in certain regions. Unfortunately, one of those regions isn't the UK.
If you are not in the UK, then go check the Xbox Games store right now, you might be in luck. Obviously this is going to get patched pretty quickly, so stop reading this crap and go grab it!
If you do find download it, please come back here and tell us what region you are in. Alternatively, if you try to download it but its not free, come back and tell us.
Update: Major Nelson has stated that this isn't a glitch as we first suspected, but in fact intentional: "Xbox One and Xbox 360 owners in select regions can download The Witcher 2: Assassins of Kings for free on Xbox.com anytime between now and February 5."