I picked up my copy friday from Gamestop. Clerk said they'd probably run out of stock by the end of the weekend. They were sold out of wii wheels. So I went to Best Buy, bought the last wii wheel available. And they told me they already sold out the game and the MK8 bundle.
That's just my experience, but I think we're looking a high sell-through.
Same experience here, difference being that German stock was in danger of running out before official launch XD