Full story here...
In order to get all of them, each shop or chain has to sign an agreement saying that they will sell out of all 20 consoles on the release date (which is December 2 over there). On top of that, the retailers must agree to sell a minimum of 2 games per console.
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“Microsoft Norway even said them selves that they’re gonna use the ‘Sold Out’ as a marketing strategy to hype the console.â€
Guess this is pretty standard marketing practise nowadays, though I haven't heard of such blatant "blackmailing" before.