The gaming hub page on NintendoWiFi.com for Mario Kart DS has recently become available to most of North America, as the populous gets their copies, and this new accessibility has had distinct effects on the "activity over the last two weeks" chart.
As you can see, all online play (by game testers, Nintendo itself, and various media organizations) has been absolutely dwarfed by the incredible surge of popularity in the last day or two due to publicly released copies. Presumably, this availability has also had server load impacts, as the official site now lists "instability" in global wi-fi matchmaking.
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