Well, I just placed my order for one of those Walmart.com bundles. I really wanted to hold out for Amazon taking pre-orders (I have enough Amazon giftcard money saved up to cover the system and a game), but it's just not looking likely and I didn't want to be left out in the cold when even Wal-Mart sells out of preorders.
Edit: One thing I would like to point, though, is that Wal-Mart is charging you the entire amount upfront when you place an order, no small pre-order fee, but all $450 (plus tax/shipping) for the Deluxe console + game + WiiMote.