Which stars had the biggest year? All this week, we've unveiled our top nine men and women of 2009 — with the winners announced today!

It's been a big year for Taylor Swift, Beyoncé, Miley Cyrus and Britney Spears, but there's not much question that 2009 was Lady Gaga's year. New York native Stefani Joanne Angelina Germanotta began the year as a hot hopeful and will end it as one of the biggest pop stars in the world. And there's no one who challenged, provoked, entertained and, well, titillated us over the past 12 months quite like she has.

Her debut album, The Fame, was released on October 30, 2008, but MTV News was on the case early, and when we spoke with her four months earlier, her vision was clear even then.

"What has been lost in pop music these days is the combination of the visual and the imagery of the artist, along with the music — and both are just as important," she said. "When I'm writing music, I'm thinking about the clothes I want to wear onstage. It's all about everything altogether — performance art, pop performance art, fashion. For me, it's everything coming together and being a real story that will bring back the super-fan. I want to bring that back. I want the imagery to be so strong that fans will want to eat and taste and lick every part of us."

And it's all come true (well, except maybe the licking part): Gaga truly made her mark in 2009 as the most remarkable pop star — and possibly the most memorable fashion figure — to come along in many, many years. She has proven herself to be both a songwriter and musician of unusual talent, — thanks in no small part to her primary producer/co-writer RedOne, whose pumping beats and soaring synthesizers drive many of her best songs — and a media-savvy public figure of equal skill. She's both a classic pop star and one very much of the moment: Her music is dance-pop in format, but with a pop flair that stretches across many different genres and generations. Her message is provocative but positive, and she's smart enough to engage her audience (with tweets and constant reminders of how much she loves her "monsters") and still always keep them guessing.

Gaga's work shows a sense of performance-art and theater that, these days, is arguably rivaled among major artists only by that of Kanye West, which is why their ultimately cancelled "Fame Kills" co-headlining tour made sense artistically (although many were baffled by it). She makes every public appearance into an event: She "died" a bloody death at the 2009 MTV Video Music Awards (after arriving with her "date," Kermit the Frog), smashed bottles over her piano at the American Music Awards, performed inside a giant gyroscope on "Saturday Night Live" and raised millions of eyebrows with the "alien disco" "American Idol" appearance that introduced her to much of the world. And her brilliant music videos evoke the eras when artists and record labels actually had big budgets to spend on them. "Pokerface" is a striking statement of intent; "Just Dance" brings the viewer into a deliciously decadent house party; and her latest, for "Bad Romance," features super-futurist sets, semi-nudity, wild costumes and the unforgettable closing image of sparks shooting out of her breasts.

All of that and much more is what made Lady Gaga MTV News' Woman of the Year for 2009.

2009 Highlights: Gaga's year began with a tour opening for the Pussycat Dolls, who were quick to say they're big fans. ... Began her first headlining tour in March. ... Collaborated with Wale, and gained even more hip-hop cred when she teamed up with Kanye West, Common and Kid Cudi on a re-take of her "Pokerface." ... Admitted that she's bisexual and paid frequent tribute to her large gay following. ... Got an early co-sign from Madonna, who attended a New York show in May with daughter and Gaga fan Lourdes, and later said she was "very flattered" to be compared with Gaga... Was nominated for nine 2009 MTV Video Music Awards and won three, and also made a memorable performance of "Paparazzi" at the show. ... Underwent a rollercoaster ride about her "Fame Kills" tour with Kanye West, which West unexpectedly announced in June and was finally confirmed months later before being cancelled in the wake of West's interruption of Taylor Swift's VMA speech. . ... Gaga quickly rebounded with her Monster Ball Tour, which kicked off in Montreal in November and continues into January before heading overseas the following month.... Decided to break out The Fame Monster,, which was intended to be a bonus disc on the re-release of The Fame, as a stand-alone disc to save her fans' money. ... Appeared with Beyoncé in B's "Video Phone" clip and duetted with her on "Telephone," a song Gaga originally wrote for Britney Spears (but Spears passed on)... and she'll close out her breakthrough year with a New Year's Eve performance in Miami, and she's likely to make a splash at the 2010 Grammys, where she's nominated for five awards.

Gaga also got a nod from President Obama, who said before she performed at the Human Rights Campaign dinner, "It's a privilege to be here tonight to open for Lady Gaga. I've made it!" Gaga later performed for the Queen of England at the Royal Variety Performance in December. ... Was stopped by Chicago police, who had some issues with her short-short pants... Collaborated with "American Idol" star Adam Lambert on the song "Fever," from his debut LP. ... Had her style called "fascinating" by top designer Vera Wang. ... And "cried like a baby" when she learned she was the first artist in the 17-year history of Billboard's Pop Songs chart to land four #1 singles ("Poker Face," "LoveGame," "Just Dance" and "Paparazzi") from a debut album.

Which stars had the biggest 2009? Our list is based on factors like music sales, box-office performance, MTVNews.com headlines and traffic, overall reach (crossover singles, appearances in movies, licensing of songs for commercials, clothing lines, etc .), plus X-factors like "impact" and "buzz. " (And no, President Barack Obama didn't make the list — we left that to the folks at Time.) This is by no means an exact science, but we think the list we've put together represents the men and women who helped make 2009 the most exciting and memorable 12 months in recent history.

As always, we want to know what youthink, so weigh in with comments below, or upload them to Your.MTV.com!