In less than 12 hours, the Xbox 360 will be released, though at many places you will have to wait until business opens at 8 or 9 in the morning.
Many people have had a chance to experience the Xbox 360, and others even have theirs thanks to one of many release contests. If you are looking at getting the Xbox 360, you might want to be there when the stores open up as they might not have one for you if you wait.
Also, for strategy sake, you might want to try a smaller location, as I know the bigger ones are going to be crowded. This is the electronic to put under the christmas tree this year, and though the cool factor of having it first is gone, you can still have it first in your neighborhood if you play your cards right. And for those thinking you can play it safe and stay home because you have a pre-order. How long ago did you order? If it was any time recently, then you probably are not going to be in the first shipment.