Same thing happened for the 360 launch. People had games and controllers and stuff a few weeks before the console came out. Kameo, for instance, came out Nov 9, 13 days before the 360 did (US release dates of course)
The Wii is being released Nov. 19, which is a Sunday. If you're one of those lucky people who consistently works M-F and has Saturday & Sunday off, it probably won't be much of a problem.