The Toys''R''Us stores are taking pre-orders for the Nintendo Wii and the Sony PS3.

You have to put $50 down to reserve either a Sony PS3 or a Nintendo Wii. Some coverage of the Toys''R''Us pre-order program indicates that it starts on Sunday, but the Toys"R"Us web site has no such starting date limitation (see image). So, you should actually be able to walk into a Toys"R"Us store today and pre-order the Wii or PS3.
See also the PS3 page and Nintendo Wii page on Toys"R"Us.
Toys"R"Us took Wii pre-orders in Canada and Australia since a couple of months.

More Nintendo Wii and Sony PS3 news.