Ashlee Simpson just debuted a hot, blonde pixie cut as she stepped out with son Bronx Mowgli yesterday. The style is super-hip, but a huge change from her most recent look where she was rocking long brown (are we calling it ombré?) hair, a la Rachel Bilson. Come to think of it, Simpson has been pretty daring in the past with her hairstyles, going from sunny blonde to deep auburn to goth, number-one-Fall-Out-Boy-fan spiky black. Take our poll and let us know which Simpson-style you love best! [Photos: WENN/Getty Images/Splash News Online...