If you didn't claim a Wii U while pre-orders were still being accepted at retailers nationwide, this may be your last chance to acquire the console on launch day.
Walmart recently kicked off this year's Layaway program, in which you can reserve a hot ticket item and pay it off little by little without worrying that it'll be sold to another customer. Among the eligible products for the program is the $349.99 Wii U Deluxe bundle, a.k.a. the only one that matters. By putting down a $5 deposit and paying 10% of the Wii U's price after tax, you can guarantee that a machine will be waiting for you through December 14. In other words, even if you don't pick up the Wii U on the November 18 launch date, you'll still have a full month to casually stroll in and polish off the remaining balance.
Wii U orders opened up yesterday and will run through November 1 or until the allocated stock dries up. I didn't share this news earlier because the general Walmart public is not yet aware of the Wii U, thus a healthy supply of reservations remain. I would call your local store just to be certain, but there's no reason why you shouldn't be able to waltz in any time this week and claim a unit.
The more selfish reason why I didn't tell your this earlier is because I didn't want you filthy mongrels clearing out the supply before I had a chance to place my order!