The folks at BodyMedia (an armband that tracks calorie burn and sleep patterns) drew data from its thousands of users and found some interesting stats. It shows how much people sleep in different months. Since this is from BodyMedia users, most of these people are engaged in weight loss programs.
I've never personally used the BodyMedia, but seen it in use with friends and co-workers, many of whom swear by it and credit it not only with weight loss but a huge increase in overall fitness. So now we know what sleep patterns they put in place to help make that happen.