This won't guarantee you a 3DS at launch, because there's people that are not professional enough to constrain the pre-orders to the available theoretical supply.

They will take like *random numbers* 2000 pre-orders and get 1000 3DS in March.

Then they will shove up your ass with the usual: "Supply is lower than initially expected, it is not retailers fault, the manufacturer is late. Shipments will be available next week"

Pre-orders of highly awaited hardware. Don't fall for that.

Thats true if you don't pre-order early enough. The pre-orders come in the same way they are made to my knowledge. meaning if you pre-order the day they start taking pre-orders and somebody pre-orders say two months later. Sure the guy who pre-ordered two months later may have to wait a few weeks but the guy who was smart and pre-ordered right aways he will have his unit day one.