Quick! Describe Mickey Mouse's personality in six words or less. Having a hard time? All right, what was the last wacky thing you saw him do? Still stumped?

Mickey is a lot of things, but specific he isn't. One of the world's most identifiable characters has become little more than a corporate mascot who is rolled out whenever the Disney company needs to sell something. Mickey is a placebo, a blank slate of a cherub upon whom children and adults alike can project their fondest make-believe fantasies. Even when he makes personal appearances, he's usually silent.

Mickey could be said to be stuck in 1955, but Disney is aware it's nearly 2010. So its image-makers, aware that Mickey's "aw-shucks" act has grown stale and won't last forever in a world filled with ironic and savvy kids, are taking a risk with their flagship character. Breaking the code Mickey has followed for the past half-century, it has authorized a new image for His Mouseness, which could turn off millions of parents who treasure the genial personality they're used to. Harking back to his early years, he'll become a colorized version of his 1930s self: wiry legs, sharp angles, a stockier belly, a whip-like rodent tail, and a peaked brow that can twist into a variety of perturbed expressions to match his flashing temper.

Epic Mickey, coming out next year for the Wii console, will feature a new Mickey based on a very old concept. In the Wii game, Mickey travels back to the black-and-white cartoon world he abandoned in the 1930s, squares off against the Walt Disney character he replaced (Oswald the Rabbit) and runs around trying to eradicate other cartoon characters with paint thinner. Then he continues his quest to other locations and scenes from Disney history.

Marketing experts, who care nothing for honoring history, are made nervous by the shift, likening the coming change to the introduction of New Coke. Seen through the prism of Disney history, that's nonsense -- if anything, it's a return to the original Coke, and this "new" Mickey is closer to what Walt Disney himself created and voiced -- but their nervousness is well-placed, because our current generation of American parents has grown used to the Placebo Mickey.