Kenneth, What is the Formula?

He delivered the news standing up. For a while, he sported sweater vests. He even tried signing off with the word ''Courage.'' Is CBS News anchorman Dan Rather now doing something, uh, different with his hair? Viewers watching the Aug. 21 broadcast of 48 Hours on events in the Soviet Union couldn't help but notice that Rather's formerly salt-and-pepper locks looked considerably darker. Rather devotees shouldn't have been completely surprised; several weeks earlier, his hair had had a slightly reddish cast. Is the unpredictable anchor dyeing in the line of duty? CBS will neither confirm nor deny. ''Considering the magnitude of the story we're covering, don't you think that's a silly question?'' says a network spokeswoman. We didn't, so we asked renowned New York celebrity hairstylist Kenneth Battelle (whose clients include Joan Rivers and Jacqueline Onassis) for an expert opinion. ''He's definitely dyeing it,'' Kenneth (who likes to be known on a one-name basis) claims. But he's all for the new style-it ''looks great,'' he says. And it's probably a lot more comfortable than a scratchy sweater.