Jay Leno says people are going to bed earlier these days. Jay Leno says 10pm is the new 11:30.
Jay Leno is wrong.
Despite the headline, I seriously doubt Jay Leno intended to be deceitful even if it was good PR for being on at 10pm. I'm sure Mr. Leno believes what he said is true. But Leno is wrong when he says that people are going to bed earlier. It is definitely true that more people are watching TV at 10pm than 11:30pm, but that's nothing new. People actually do go to sleep. But are they going to sleep earlier?
The Nielsen data when it comes to television viewing doesn't indicate that people are going to bed earlier. In fact, it indicates that people are generally going to bed at the same time they always did, and if anything are staying up a little bit later now!
What the data shows is a decreasing trend of viewership between 10pm-11pm (not great news for Leno's new timeslot), and increasing viewership between 11:30pm-12:30am. That holds true both as a one year trend and a five year trend.
According to Nielsen data, 6% fewer 18-49 year olds are watching TV between 10pm-11pm than were watching 5 years ago. 4% fewer 18-34 year olds are watching between 10pm-11pm than five years ago. If you want a broader view, looking at 25-54 year olds, viewing between 10pm-11pm is down 7% over the last five years.
Meanwhile, the trend is up for viewing between 11:30pm-12:30am over the last five years among 18-49 year olds (1% increase) and 18-34 year olds (5% increase) and is completely flat among the broader 25-54 demographic.
All data above is based on LIVE viewing only, but since the discussion was about whether people were going to bed earlier, bringing DVR viewing habits into the mix didn't make much sense.
 Some have made the case that the decreases in the 10pm hour mean that Leno is right. Obviously, I don't think so. I attribute the decreases in the 10pm hour almost entirely to DVR proliferation. But sure, it could be a variety of things from videogames, reading, watching DVDs and yes, some people going to bed earlier. But if the trend of live viewing is up at 11:30pm, it's hard to ascribe any merit to the notion that people are going to bed earlier overall.