Last Night's Look: Hit or Miss?

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ASHLEE SIMPSON

What baby weight? The new mom shows off her svelte figure in a sexy peekaboo lace minidress and patent ankle strap pumps at a T-Mobile party in Los Angeles.

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MARIAH CAREY

She recently celebrated her first anniversary with husband Nick Cannon, but the signer is still a blushing bride in a body-hugging beaded white gown for the Precious photo call at the Cannes Film Festival.

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KIM KARDASHIAN

The reality vixen takes a futuristic approach to fashion in her sharp-shouldered blazer, black pants and pumped-up ponytail at the T-Mobile party in L.A.

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JESSICA ALBA

The actress goes for a preppy summer look in her crisp white button-down and pleated trouser shorts accessorized with chunky platforms, a blue Ferragamo bag and a statement headband for a day out in Beverly Hills.

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WHITNEY PORT

Always the fashionista, the reality star hits some major spring trends in her satin jumpsuit and orange patent pumps for a party in New York City.

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HEIDI MONTAG

The Hills star trades in her bridal trousseau for an off-the-shoulder black ruffled dress, cinched at the waist with a corseted buckle belt, and matching platform heels for the T-Mobile party in L.A.

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AMY ADAMS

The actress sets off her fiery red hair with a violet RM by Roland Mouret gown for the premiere of Night at the Museum: Battle of the Smithsonian in Washington, D.C.

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HILARY DUFF

The star keeps it simple in a long blazer and white blouse over black leggings for an event honoring people with AIDS at the Empire State Building in New York City.

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ELIZABETH BANKS

The actress gives her navy-and-black sequin Andrew Gn gown a vintage feel with soft curls and statement cuffs also by the designer Spring Fever premiere during the Cannes Film Festival.

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EVA LONGORIA PARKER

The star dazzles at PEOPLE EN ESPAÑOL’s 50 Most Beautiful event in N.Y.C. on Wednesday in a bejeweled minidress and nude pumps.

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JENNIFER LOPEZ

The actress stays stylish on the set of her film The Back-Up Plan in an off-the-shoulder teal jersey dress and brown T-strap platforms in L.A.

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KIM KARDASHIAN

It’s all about mixing high and low as the reality star hits the Maxim Hot 100 celebration in Santa Monica in a figure-hugging white H&M dress, which she pairs with luxe Jil Sander shoes and a Christian Louboutin clutch.

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TORI SPELLING

The reality star shows off her svelte figure in a canary yellow frock with ornate detailing at the neck and strappy gold sandals to celebrate her cover of Cookie magazine.

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ELIZABETH BANKS

The actress is red hot at the premiere of Up in Cannes in a one-shoulder Armani Privé gown with elegant gathering at one hip, classic Chopard gems and Marcel waves.

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AUDRINA PATRIDGE

Making her legs the focus, the reality star hits the Maxim Hot 100 party in Santa Monica in a midnight blue Doo-Ri minidress and jewel-encrusted Giuseppe Zanotti for Balmain sandals, topping off the look with a black Kris Van Assche tuxedo jacket.

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ROBIN WRIGHT PENN

The Cannes jury member is elegant at the opening night premiere of Up in a liquid-silver Elie Saab couture gown, Jimmy Choo sandals and Louis Vuitton diamonds.

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HEIDI MONTAG

For Maxim’s Hot 100 celebration in Santa Monica, the Hills star gets sexy in a light blue bandage dress paired with a metallic necklace, clutch and booties.

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TILDA SWINTON

The edgy fashion muse goes monochromatic on the Up red carpet in Cannes in a maroon ensemble including a floor-sweeping charmeuse skirt and jacket.

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NICOLE RICHIE

What baby bump? The jewelry designer slips into a flirty printed mini and peeptoe booties at groundbreaking ceremony for a new organic gardening program for L.A. schools in partnership with the Environmental Media Association and the L.A. Unified School District.

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JESSICA BIEL

After glamming it up in 3.1 Phillip Lim for her movie premiere, the actress is back to casual in an oversized plaid shirt, leggings and boots, topped off with a leather jacket, for a stroll through Manhattan.

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EVA LONGORIA PARKER

The actress makes for a bright sight in her fitted coral sheath, nude platform heels and Gustto clutch as she heads to dinner at her restaurant Beso in L.A.

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ISLA FISHER

The actress leaves constant companion, daughter Olive, at home for a day of shopping in her sweet floral cami, ripped jeans and purple cardigan.

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MICHELLE TRACHTENBERG

She might be back to her old scheming ways on the Upper East Side, but the Gossip Girl star is perfectly sweet in her navy blue-topped pencil dress and nude peep-toes for a NBC event in Hollywood.

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HAYDEN PANETTIERE

Panettiere tops her faded gray jeans off with a chic tuxedo blazer with rolled-up sleeves for a night out in London.

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REESE WITHERSPOON

The Avon global ambassador sports a sharp red Temperley London sheath and black patent pumps at a breast-cancer charity event for the brand in San Francisco.

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JESSICA BIEL

The Easy Virtue star is perfectly chic in her one-shouldered 3.1 Phillip Lim gown and Louis Vuitton jewelry at the film’s N.Y.C. premiere.

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HEIDI MONTAG

The newlywed matches her bold blue snakeskin bag to her cobalt top while out shopping in L.A. with husband Spencer Pratt (not pictured).

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DEMI LOVATO

While being honored as the ambassador of education for the American Partnership for Eosinophilic Disorders, the Disney Channel star dons a sweet black halter dress, Swarovski jewelry and black pumps.

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MICHELLE MONAGHAN

The actress goes edgy in her panné velvet marigold Calvin Klein Collection dress and chunky black sandals at the Free Arts NYC Annual Art Auction Benefit sponsored by Calvin Klein.

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KRISTIN DAVIS

The Sex and the City star attends the Modern Bride 25 Top Trendsetters Awards Dinner in a summery yellow frock from her own clothing line for Belk.

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MOLLY SIMS

The star gets a jump on summer in her softly shimmering Calvin Klein Collection white sheath and zip-front black sandals at the Free Arts NYC event.

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DITA VON TEESE

The burlesque star helps H&M launch their T-shirt collaboration in a low-cut black Elie Saab dress and towering heels.

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JENNIFER LOPEZ

For this year’s Noche de Niños gala in Beverly Hills, J.Lo gets bright in a teal Temperley London gown with blouson sleeves, strappy heels and Neil Lane jewels – including 20-carat diamond earrings.

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KIM KARDASHIAN

The reality star is elegant in a figure-skimming gray gown, satin clutch, Amrapali earrings and ornate cuff at the Race to Erase MS event in Century City, Calif.

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JESSICA ALBA

Looking like one gorgeous mama, the actress strolls in L.A. on Mother’s Day in a floral-printed frock, blush cardigan and buttery bag.

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NATALIE PORTMAN

Bringing Hollywood glamour to Washington, the politically active actress heads to the White House Correspondents’ Association Dinner in D.C. in a stunning black gown with panel collar detail, organza shawl and satin clutch.

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JESSICA BIEL

Revlon’s newest face keeps it casual while shopping in N.Y.C., pairing low-slung trousers with a white tee, ruffled jacket and flats.

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EVA LONGORIA PARKER

The actress dazzles at the White House Correspondents’ Association Dinner in D.C. in a blush-colored Ports 1961 dress interwoven with shimmering threads, sparkling H. Stern earrings and a cuff.

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VANESSA HUDGENS

Celebrating the launch of Diesel’s latest men’s fragrance, Only the Brave, in Hollywood, the High School Musical 3 star musters her fashion courage and goes for a cropped look with rolled-leg Diesel jeans, midriff-baring tank, black booties and a metallic clutch.

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DEMI MOORE

Draped in an elegant champagne chiffon Versace gown, metallic Roger Vivier clutch and stunning Neil Lane jewels, the actress shines at the White House Correspondents’ Dinner in D.C.

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SOPHIA BUSH

One Tree Hill’s resident fashion icon, gets haute for Catherine Malandrino’s Mediterranean Night Dinner in L.A. in an elegant cream-and-black frock by the designer festooned with slender chains.

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RASHIDA JONES

The Parks and Recreation star is all ruffled up for the White House Correspondents’ Dinner in a black drop-waist dress, simple sandals and elegant jewelry.

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