Prior to The Jay Leno Show taking over NBC's 10pm hour on weekdays, the network wasn't exactly burning up the ratings, and Jay's not doing much worse so far.
NBC's non-sports averages for 10-11pm weekdays for the 52 weeks prior to the debut of The Jay Leno Show were a Live+SD 2.2 adults 18-49, a 2.7 adults 25-54 rating, and 6.9 million average viewers. Not a very high standard of performance.
Unfortunately, Nielsen no longer provides Live+SD season averages to us. Instead they provide "Most Current" averages, which are a combination of Live+SD data for recent episodes and Live+7 day for episodes more than 2 weeks old.
Given that the comparison is apples to oranges (but all I've got), here are The Jay Leno Show's "Most Current" averages through November 1, 2009.
Monday, 2.2 adults 18-49 rating, 7.235 million avg. viewers,
Tuesday, 2.3 rating, 7.058m
Wednesday, 2.0 rating, 7.053m
Thursday, 1.9 rating, 5.689m
Friday, 1.5 rating, 5.935m
Overall through 11/1/09: 1.98 adults 18-49 rating, 6.594m avg. viewers
Update: Julia calculated the Live+SD overall averages: 1.92 A18-49, 6.387m viewers
Note that Jay's show is very lightly DVR viewed (three of five episodes in the latest week we have data for had zero ratings increase between Live+SD and Live+7) which makes the Live+SD to Most Current comparisons more valid than for most broadcast primetime shows.
Those numbers are skewed up by the big premiere week, but they've also come during the most competitive time of the year, and they have been trending downwards, so the averages don't tell the entire tale.
Lot's of questions remain. What will Leno's ratings be during periods of sustained repeats by the competition during the regular season? What will they be during the summer?