Reuters wrote an amusing but also enlightening story about NBC's woes over ratings and false promises of their supposed dedication to the development of new programs. It's funny because NBC just replaced five hours of scripted programming per week to make room for Jay Leno's ego. The enlightening part is the network-wide loss in viewers from 2008-2009. According to Reuters, NBC has jettisoned over 11% of its prime-time audience compared to 2007.
That's just about how much Heroes, their most popular scripted drama, has lost over that same period. It reminds me of Rudi Giuliani back when he was Mayor of New York City. He would go around telling anyone that would listen that he was responsible for a big reduction in violent crime in NYC while omitting the nearly identical national falloff over that same period.
If NBC lost 11.2% of its viewers and Heroes has lost something like 10%, suddenly it looks like Heroes isn't having the kinds of problems that everybody thinks they are, and changing talent behind the scenes isn't the solution this network needs right now. They are already down three producers (one left but coming back, two fired) that were there from the beginning, and there's a rumor out there that one unnamed star is ready to walk.
Perhaps it's time to stop blaming good shows for losing viewers when the networks are also losing viewers overall to cable, and to people just plain leaving.