Style Watch PollLast Night's Look: Hit or Miss?

Vote on this week's styles including Ashlee Simpson, Christina Aguilera and more stars! You decide – are they fashionistas or flops?

Credit: Jeff Kravitz/FilmMagic

Updated: Saturday Dec 11, 2010 | 06:00 AM EST

The svelte singer glams it up in a sexy satin Dolce & Gabbana gown before taking the stage at an Ambassadors for Humanity gala in Hollywood.