It got slammed by critics, but the ratings were very strong.

I feel bad for Conan.

The debut of NBC's high-wire-act 10 p.m. comedy show was seen by 17.7 million viewers and pulled a 5.1 preliminary adults 18-49 rating.

 

That's 34% stronger in the adult demo than the final national household rating for Conan O'Brien's

"Tonight Show" debut last June (9.2 million viewers and a 3.8 adults 18-49 rating) and 50% higher than Leno's final "Tonight Show" last May (11.9 million viewers and a 3.4 rating).

...

http://www.thrfeed.com/2009/09/jay-leno-show-premiere-ratings.html

Critics slam `Leno Show,' call it `Tonight' rehash:

http://news.yahoo.com/s/ap/20090915/ap_on_en_tv/us_aftermath_leno_premiere