MK Wii is out of stock in my town at at least two retailers. One of them had stock a week ago and I have never seen them sell out of a Wii game before. They were my super-secret dealer when everybody else was out of No More Heroes. Luckily, they did have Boom Blox. Between that and WiiWare, I should be able to wait a little longer for Kart.
@ the OP
Yes, we know GTA IV wins the week one award. Halo 3 also won the week one award against Super Mario Galaxy, but Galaxy is now set to overtake Halo 3 sales before the end of this year. I'm not saying that Kart will necessarily outsell GTA IV, as I'm sure GTA IV will have better legs than Halo 3, but first week sales are a poor indication of overall success, especially when comparing to Nintendo titles which tend to squeeze into top-10 lists months after initial release.
Mario Kart doesn't have to destroy GTA IV, it just has to remind people that GTA IV won't destroy the Wii, and that the platform still has incredibly fun games coming out for it. And yes, there are even a few gamers who deferred purchasing GTA IV to buy MK Wii. They've posted in this forum.

"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
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