My own anecdotal evidence suggests that there are two classes of people with respect to sleep: those with kids under ten and the rest of us. A new Gallup survey doesn't disprove this, but it does show how the working poor and women are - surprise! - among most exhausted. The one genuine surprise: the over 65s say they are less rested than the rest of us.
This article available online at:
http://www.theatlantic.com/daily-dish/archive/2010/02/sleep-rest-and-class/190708/