It’s not enough that he’s obviously in the tank for the left and doesn’t ask the Democrats any of the tough questions when he interviews them, they want him to even give up the appearance of objectivity:

Some are ticked because he led the effort internally at the Peacock to remove Chris Matthews and Keith Olbermann from both commentating and anchoring big election events. And he has served as what some call “shuttle diplomacy” with the McCain campaign, promising them they could get fair coverage from NBC.
And MoveOn started a campaign to call out Brokaw out for citing an old poll that favored McCain in a recent “Meet the Press.” Media Matters agrees.
Then there’s Brokie’s post-debate remarks Thursday:
“I think they’re wolfing it up in Alaska tonight and all the parties across the country for the McCain campaign. In terms of our theatrics and personal style out there, you can see why she’s such a successful politician in Alaska.”
He said Palin “did herself a lot of good and probably her ticket some good as well.”

(via)
BTW, I think Charlie Rose would be an improvement over Brokaw. He actually asks pretty decent questions, he’s a good interviewer. It might actually be interesting for a change.