This has been true. But why? The Times has lied for decade. Why only now is it an issue?
Why now? Because only now have they been caught so red-handed, and it started with Jayson Blair. That just got all these self-important no-talents to start fighting amongst themselves, which is allowing a lot of other "stuff" to start leaking.
Well, that and the fact that the internet, talk radio and cable stations like Fox News Channel, have finally provided this market the competition that has long been needed. And just like people fleeing Communist countries, when given a choice, people will flee the leftist media.
For the same reasons that all the other issues we on the right have raised for years about fraudulent journalistic "ethics" never became issues until after Fox News, talk radio, the Internet, etc came along. The system worked just fine for the journalists (the public was merely there to shut up and consume), so it was never an issue. Now that we've got choices and have both the ability to question the questioners, and ignore them entirely if we deem them too biased, they are being forced to adapt or die.