According to bol.com a dutch retailer the wiifit is in such high demand that the next shipment is expected to hit in week 31 ( end of july ) and bol.com just send the following mail to customers that ordered.
translation:
Be aware: we already recieved a enormous amount of orders for this already published product which we will deliver in the coming months. For these deliveries we are depended on the availablity of the product from our distributors. We expect to have free stock for this product upcoming september.
How Insane is that?