Nancy Pelosi, Hillary Clinton, and newly appointed Supreme Court justice Sonia Sotomayor were some of the most powerful people in US politics this year. Overseas, 83-year-old Queen Elizabeth II continued her reign as the oldest living monarch in British history by counseling the prime minister and welcoming foreign guests ranging from the Obamas to Lady Gaga. Meanwhile, Germany's Angela Merkel represented women on the international stage as the only female head of state in the G8.
Of course politicians don't hold all the power. Oprah Winfrey continued to influence people around the world (and will for another year at least), while Tyra Banks tried to become the next big thing by working her brand and influence. And while Marissa Mayer might not be a household name, as the head of search at Google, she probably has the biggest impact on our everyday lives. (Don't forget to check out all our other Best of 2009 coverage!)