Most Powerful Women take New York

“Betting on the Future.” That’s the 2009 theme of Fortune’s Most Powerful Women, who convened in New York City last evening for a mega-celebration and some very smart conversation. I’m not sure I belong on stage with three superstars under 40: Bank analyst Meredith Whitney, Google’s (GOOG) Marissa Mayer, and Goldman Sachs’ (GS) Dina Powell. But there I was (at age 49), talking with them them about how they’ve navigated their careers and how they view the future.

It was an insanely inspiring evening, thanks also to 32 young women from 23 developing countries. This happened to be the last night in the U.S. for these participants in this year’s Fortune/U.S. State Department Global Women Leaders Mentoring Partnership. These international women are nominated by the State Department’s embassies in developing countries and chosen by Fortune to shadow American women leaders each May. Some of this year’s mentors — including Time Inc. (TWX) CEO Ann Moore, Fidelity Personal Investing president Kathy Murphy, American Express (AXP) execs Joan Amble and Susan Sobbott — were with us last evening.

So were plenty boldfaced names: Tina Brown, Nora Ephron, CNBC’s Becky Quick, CNN’s Christiane Amanpour. My Postcards colleague Jessica Shambora sat beside Sheri McCoy, Johnson & Johnson’s (JNJ) Worldwide Pharmaceuticals chairman, who is No. 44 on Fortune’s Most Powerful Women list.

A few Best Moments from the evening:

Best Career Lesson: Mayer, Google’s vice president of search products and user experience, talked about juggling 14 job offers after she graduated from Stanford. She interviewed with Google founders Sergey Brin and Larry Page and guessed that their start-up had “a 2% chance of succeeding,” she said. But she also figured, “I’ll learn more failing at Google” than succeeding at a well-established, stuck-in-its-ways company. She took a risk, And look at where it got her. At 33, Mayer is the youngest person ever to make Fortune’s Most Powerful Women list.

Smartest Industry Outlook: Meredith Whitney, who is No. 35 on our MPWomen list and made Fortune’s cover last August, said that more banks will fail as the economic recovery stumbles and some giants fail to adapt. The survivors: nimble companies that revamp their business models. One that she bets will succeed: American Express. (Click here to see Whitney talking with CNNMoney’s Poppy Harlow.)

Most Dynamic Duo: Gayle King, O magazine editor at large and Oprah Winfrey’s best friend, who brought as her “rising star” guest her daughter Kirby. A 23-year-old Stanford grad, Kirby Bumpus is pursuing her Masters in Public Health — and this summer doing an internship with teens in Harlem, teaching them about sex education.

Most Moving “Greatest Mentor” tribute: Rica Rwigamba, who runs an eco-toursim company in Rwanda, spoke about her mother and drew tears and standing ovations. This charismatic entrepreneur, who was one of the 2009 mentees, told a story about her mother returning to Rwanda after the country’s genocide and finding a new home for her husband and children. After Rika’s tribute, CNN”s Christiane Amanpour, sitting beside her, talked about her “Greatest Mentor.” She started by citing the remarkable success of women in a revived Rwanda today: Women hold 56% of the seats in Parliament. CNN’s chief international correspondent segued into a tribute to her mentor: Ted Turner, who built CNN.

Best Party Crasher: Cecilia Attias, who divorced French President Nicholas Sarkozy in 2007, remarried and has moved to Manhattan. She came with Jocelyne Attal, the former CMO of Avaya who now has her own marketing firm, JAgency. Surprise! Attias’s arrival was particularly dicey since the only dinner seat we had for the former First Lady of France was at a way-in-the-back table. Frantically, we tried to make the necessary switches. We couldn’t do it in time before everyone was seated. I have to say, Attias was lovely and most gracious. She thanked us and said she was thrilled that we were able to accommodate her.

We were happy to have her with us…along with 180 other extraordinary women who define power broadly and reach out globally to try and make the world a better place.

Stay tuned to Postcards for video from the evening. Meantime, have a good weekend!