Last Night's Look: Hit or Miss?

heats up the Latin Grammy Awards in Las Vegas in a sparkling keyhole gown by Andrew Gn that hugs the megastar’s every curve and a Cecelia clutch.

shows her support for Project Runway runner-up Mondo Guerra, donning a dotty custom gown for the Black Swan screening during Audi’s AFI Fest 2010 in Hollywood.

No vinyl here! The is Purr-fect in a sweet purple frock and Dolce & Gabbana heels during the London launch of her debut scent, Purr.

The of the Bambi Awards shakes up Potsdam, Germany in a luminous, one-shoulder Halston Heritage dress, fierce strappy Nicholas Kirkwood platforms, Fred Leighton diamonds and a beaded clutch.

continues to captivate London with her grown-up style, rocking a racy lace Rafael Lopez for Atelier Mayer minidress with a feathered skirt and Charlotte Olympia heels at the Harry Potter and the Deathly Hallows: Part 1 world premiere.

The Black Swan tries a springtime look in a pink floral chiffon Rodarte confection, gold Dior sling-backs, Fred Leighton jewels and a ruby clutch at her movie’s Audi’s AFI Fest 2010 screening in Hollywood.

rocks out in a long-sleeved beaded sparkler by Jenny Packham – check out that racy cut-out! – and metallic sandals before playing mistress of ceremonies at the Rock for the Cure benefit in Las Vegas.

The actress is a breath of fresh air in a floral Carolina Herrera fishtail gown and Cartier jewels at the Latin Grammy Awards in Las Vegas.

The Versace fan leaves her Mad Men looks behind, opting for an ultra-sleek LBD with side cutouts and a high bouffant at a dinner with Donatella Versace in London.

The of Mark cosmetics makes her mark in a ladylike tweed sheath at the brand’s beauty event in New York.

The laid back actress shimmers in an elegant pink dress with a draped skirt at the Night Catches Us New York premiere.

gives her pixie cut a red carpet spin, pairing a one-shoulder velvet Vionnet dress with crimson lips and edgy accessories at a promotional event for Harry Potter and the Deathly Hallows: Part 1 in London.

Everything’s coming up roses for , who rocks a floral bustier by The Blonds, a tight pink mini and blue platforms before performing at the Victoria’s Secret Fashion Show taping in New York.

The Country Strong hits the CMA Awards in Nashville in an Atelier Versace gown with a side cutout – and one very high slit!

Also at the CMA Awards, the was big-city stylish in a gray tulle gown – with lots of ruffles! – by Talbot Runhof and a Swarovski clutch.

looks regal in a sleek updo and a black high-neck gown at a Perfumania event in New York celebrating her appearance on The Apprentice.

takes a detour from the Upper East Side to head down South for the CMA Awards in a trailing, draped Emilio Pucci gown with Cathy Waterman jewels and Jimmy Choo peep toe platforms.

The Other Guys has us green with envy in her baroque strapless dress and black platforms – both by Prada – at the movie’s photo call in Madrid.

The CMA Awards is red hot in a draped Monique Lhuillier gown with a sweetheart neck, Neil Lane jewels and Jimmy Choo sandals.

Before co-hosting the 2010 Soul Train Awards in Atlanta, the actress flaunts an edgy LBD with a sculpted bodice on the red carpet.

The actress keeps it chic in a one-shoulder ASOS LBD and black pumps on the pink carpet at the Victoria’s Secret Fashion Show taping in New York.

Va-va-vroom! The showcases her enviable shape in a black Elie Saab dress with embellished skirt at an Audi-hosted AFI Film Festival event in Hollywood.

The celebrates being single in a geometric sequined mini and Casadei triple platform pumps at the Kardashian MasterCard launch in N.Y.C.

The shaded lightens up, opting for a yellow frock, satin cap-toe pumps and slicked-back tresses while in the U.K.

The abandons girly frocks in favor of a sparkling halter ZSpoke by Zac Posen dress and Neil Lane jewels at the BMI Country Awards in Nashville, Tenn.

The keeps it simple in a strapless gunmetal dress and patent pumps at the People’s Choice Awards announcements in Los Angeles.

The trades her modern mini for a sweeping brown and taupe gown with drop earrings and a cuff bracelet at the BMI Country Awards.

Is she a fashion “do”? The actress accents her tiered floral Dior minidress with bright pink lips and a quilted blue bag at the New York Moves Power Women event in N.Y.C.

tucks her cream blouse into a high-waisted mini to celebrate her new clothing range, Miley and Max for George, at an Asda supermarket in the U.K.

Banks shows off her trim midsection in a fringed cut-out Versace LBD, Stephen Russell jewels and strappy sandals at the N.Y.C. premiere of The Next Three Days.

keeps it casual in a lacy floral top and side-zip denim on the L.A. set of Extra.

The aspiring country star brings Hollywood glamour to the Nashville premiere of Country Strong, where she spotlights newly toned physique in a chic black Chado Ralph Rucci dress with sheer, peekaboo trim and matching Lanvin shows.

plays a modern siren in her shirred gown with a thigh-high slit, which she accents with Cartier jewels, golden Brian Atwood pumps and sexy waves at Glamour magazine’s Women of the Year Awards in N.Y.C.

in Tennessee? The Upper East Side darling makes a statement in a crocheted black and magenta Marc Jacobs gown with golden underpinnings and Cathy Waterman gems at the Nashville premiere of Country Strong, in which she has a supporting role.

cuts a sexy silhouette in a one-shoulder scarlet gown by Zac Posen with a daring slit, oodles of Cartier diamonds and fire-engine red Casadei pumps at the Glamour Women of the Year Awards in N.Y.C.

You’ve got to have ! The singer shows stylish support for hubby at the Country Strong premiere in a modern black-and-white mini with origami pleating, Solange Azagury-Partridge jewelry and basic black pumps.

gives her new bob some extra bounce while appearing on Late Night with Jimmy Fallon in a belted 3.1 Phillip Lim LBD with jewel-encrusted neckline, patent belt and opaque tights.

The Glee star keeps it flirty in a watercolor cocktail dress, Caleo jewels and patent pumps at TV Guide’s 2010 Hot List party at the W Hollywood Hotel.

Debuting a darker do in N.Y.C., glams it up for a VH1 Save the Music Foundation gala at Cipriani Wall Street in a dusty blue chiffon gown, House of Lavande cuff and ruby lips.

The Glee cutie plays with contrast, pairing a chambray button up with a glittering gold sequined Nanette Lepore skirt and silver sandals at the TV Guide Hot List party in Hollywood.

makes the most of basic black, pairing her belted A-line LBD with sky-high satin pumps outside the Late Show with David Letterman.

Before rocking out with Bon Jovi at the MTV Europe Music Awards in Madrid, made her entrance in a show-stopping tulle Marchesa mermaid gown.

The MTV Europe Music Awards raises the style bar – and her hemline! – in silky chocolate Emilio Pucci dress with trailing train.

Also at the MTV Europe Music Awards, donned a floor-length D&G halter-neck dress adorned with ruffled tiers and a black bow.

brings high shine to the New York Morning Glory premiere in a strapless gunmetal Lanvin dress and studded mesh heels.

The Calvin Klein underwear model covers up her curves in a chic LBD, printed clutch and Mary Jane heels for the Abel screening at Audi’s AFI Fest 2010 in Hollywood.

The shakes it in a plunging black-and-gold sequined Pamella Roland dress before taking the stage at the MTV Europe Music Awards in Madrid.

It’s a fashion-forward look for the actress, who graces the 2010 Freedom Awards in Redondo Beach, Calif. in an embellished nude top and a tiered tea-length black skirt – both by Derek Lam – with Cartier jewelry and Brian Atwood heels.

She’s got just the ticket! Pairing her red and black sequined dress by Jeremy Scott with equally shiny purple Sergio Rossi peep toes, the newly wed makes a flashy entrance at the MTV Europe Music Awards in Madrid.

Giving a peek of her toned tummy, the 90210 vixen is simply sassy in one-sleeve black mini by Donna Mizani at the Cheetah Vision, Hannibal Pictures & Emmett/Furla Films AFM party in Santa Monica.

Showing fashion sense beyond her years, the rising starlet dons a chic silhouette in a black-and-white digital print and Roger Vivier navy satin d’Orsay heels at Audi’s AFI Fest 2010 Los Angeles Times Young Hollywood Roundtable in Hollywood.

The bursts onto the scene in a tropical blouse tucked into pleated-front Aryn K khakis paired with torn-up tassel loafers for the Beverly Hills Fashion Festival.

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