Sure the press is biased. What else is new? Ronald Reagan won the Cold War without firing a shot, and without the support of the mainstream media, in part because he was a great communicator. And it's hard to remember right now, but a few years ago Rumsfeld was a media darling. Today he's a bum.
IMHO this change reflects Rumsfeld's own decisions.
First and foremost was his decision to replace Tori Clarke as head PR honcho in the Pentagon. After Clarke left "to spend more time with her family," Rumsfeld's positive image began to sag. And there's nothing that Larry DiRita, a talented numbers-cruncher policy wonk who used to work on another floor of the Heritage Foundation when I was there, can possibly do to fix that. Good PR requires a good PR person in charge. He's just not a good PR person. And if your PR person isn't the best, what does that say about the rest of the operation? It's PR 101...
So, instead of lashing out at the messenger, maybe Rumsfeld might show us that he's willing to do some soul searching himself...