It should come as no surprise that Forbes magazine named Oprah Winfrey its most powerful celebrity. After all, last year, she banked an unbelievable $275 million. Though ratings for her talk show have slowly declined, Oprah is smart enough to pursue other business ventures to ensure her success. Next year, she'll unveil The Oprah Winfrey Network, which is partnered with Discovery Communications. She has a 3 year, $55 million deal with XM Radio and her Harpo production company is responsible for the success of The Dr. Phil Show and The Rachael Ray Show. Tiger Woods, Angelina Jolie, Beyonce Knowles, and David Beckham rounded out the top 5. This year, tweens made a strong showing on the list, especially those that hail from The Disney Channel.