the G-man wrote:
bigdaddy is correct, re: the Olympics.
NBC, rightly or (in my mind) wrongly assumes that Fallon will do significantly better than Leno in "the coveted 18-49 demographic."
In addition, Fallon has (unlike Conan at the time he took over TTS) the backing of Lorne Michaels, one of the most powerful people at the network.
Conan was very much supported by Lorne Michaels during the tonight show debacle. Problem was that the core executives in charge at the time, who were very much fired when NBC got bought by a new company, we're not fans of Lorne and had the support of the parent company executives. The new parent company, after firing the executives behind that situation, basically gave Lorne total controls over NBC late night programing.