Another day, another major hair color change for two A-list stars.

After dyeing her hair red back in May, Scarlett Johansson showed off a fresh golden blonde shade while promoting her new movie, We Bought a Zoo, on the Today Show in New York City on Monday. Clad in a cobalt blue dress, the actress, 27, rocked a ladylike curled bob.

PHOTOS: Biggest celeb hair makeovers of 2011

And over the weekend, color chameleon Katy Perry, 27, debuted her latest look (as well as some impressive comedy skills) on Saturday Night Live. The pop star, who's gone from black to red to blonde to lavender and most recently to a mix of blonde and pink, is now sporting a pale blonde hue with a blue streak in the front. Perry also chopped off several inches of hair last week, working an edgy razored bob.

PHOTOS: Katy Perry's hair evolution

Tell Us: Do you think these stars look better as blondes?

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