Im not sure if anyone said this yet, but Nintendo is doing pulse shipments instead of burst shipments (I think i just made those terms up). Anyways, this means that they are doing a bunch of smaller shipments as opposed to one giant shipment every once in a while. This means that it will be easier to find the wii u in stock than the wii because once the wii was out, the next shipment didn't come for a while which created a supply/demand funnel. The way it is now eliminates that funnel and therefore creates less of a frenzied environment and allows people to pick it up when they want to.
We will see what effect this has on sales, until then, this data is useless