A tipster wonders if NBC is going softer as CBS tries to get harder.

In an e-mail, they write: "While Katie Couric has spent two nights taking a hard look at cancer from every angle -- including an interview with the president of Memorial Sloane-Kettering Cancer Center -- Brian Williams had an in-studio interview with Sheryl Crow (who had also been on the morning programs) on Wednesday. And that was after part three of NBC's series on marriage and 'the state of our unions.' What would have been the reaction if Couric had done that?"

> Update: 5:08pm: "CBS may have concentrated on cancer, but they still found time for Lara Logan's tigers feature, Bill Whitaker's story on children’s TV ads and junk food and Katie Couric's clips of Karl Rove acting silly. A couple of days does not a trend make," Andrew Tyndall responds...