Katherine Heigl arrives at the premiere of "27 Dresses."Jeffrey Mayer/WireImage.com - Friday, February, 1, 2008, 10:1 PM

Katherine Heigl arrives at the "The Late Show with David Letterman".Jim Spellman/WireImage.com - Friday, February, 1, 2008, 10:1 PM

Josh Kelley and Katherine Heigl arrive at the premiere of "27 Dresses."Jeffrey Mayer/WireImage.com - Friday, February, 1, 2008, 10:1 PM

Katherine Heigl arrives at the Advocate Magazine 40th Anniversary Party at Republique club.Jean Baptiste Lacroix/WireImage.com - Friday, December, 14, 2007, 9:14 PM

Katherine Heigl and Barbara Walters on Barbara Walters Presents: The 10 Most Fascinating People of 2007.ABC/Donna Svennevik - Wednesday, December, 5, 2007, 9:5 PM

Katherine Heigl and Kevin Dillon during the 59th Annual Primetime Emmy Awards at the Shrine Auditorium on September 16, 2007 in Los Angeles, California.John Shearer/WireImage.com - Monday, September, 17, 2007, 6:17 PM

Katherine Heigl arrives at the 59th Annual Primetime Emmy Awards at the Shrine Auditorium on September 16, 2007 in Los Angeles, California.Jeff Vespa/WireImage.com - Monday, September, 17, 2007, 2:17 AM

Katherine Heigl and Kevin Dillon during the 59th Annual Primetime Emmy Awards at the Shrine Auditorium on September 16, 2007 in Los Angeles, California.John Shearer/WireImage.com - Monday, September, 17, 2007, 5:17 AM

Katherine Heigl poses with her Best Supporting Actress in a Drama Emmy in the press room at the 59th Annual Primetime Emmy Awards at the Shrine Auditorium on September 16, 2007 in Los Angeles, California.Steve Granitz/WireImage.com - Monday, September, 17, 2007, 5:17 AM

Katherine Heigl arrives at the 59th Annual Primetime Emmy Awards at the Shrine Auditorium on September 16, 2007 in Los Angeles, California.Jeff Vespa/WireImage.com - Monday, September, 17, 2007, 12:17 AM

Katherine Heigl stars as Isobel "Izzie" Stevens on Grey's Anatomy.ABC/Bob D'Amico - Wednesday, September, 12, 2007, 6:12 PM

Katherine Heigl is No. 6 on our list, but the question on everyone's minds is whether her character Izzie will continue her romance with her married best friend George.Jeffrey Mayer/WireImage.com - Monday, August, 13, 2007, 5:13 PM

Katherine Heigl at the 6th Annual GM Ten.Gregg DeGuire/WireImage.com - Monday, July, 2, 2007, 11:2 PM

Katherine Heigl at The 58th Annual Primetime Emmy Awards.Steve Granitz/WireImage.com - Friday, July, 6, 2007, 12:6 AM

Katherine Heigl at The 58th Annual Primetime Emmy Awards.Steve Granitz/WireImage.com - Friday, July, 6, 2007, 12:6 AM

Katherine Heigl at the 13th Annual Screen Actors Guild Awards.Gregg DeGuire/WireImage.com - Monday, January, 29, 2007, 8:29 PM

Josh Kelley and Katherine Heigl at the In Style and Warner Bros. 2007 Golden Globe After Party.John Sciulli/WireImage.com - Tuesday, January, 16, 2007, 10:16 PM

Katherine Heigl at the 64th annual Golden Globe Awards.Steve Granitz/WireImage.com - Tuesday, January, 16, 2007, 3:16 AM

No. 3 is Katherine Heigl who is having quite a summer with the success of Knocked Up and lots of talk of her engagement. She'll be back on the small screen for Season 4 of Grey's Anatomy in the fall.Steve Granitz/WireImage.com - Tuesday, January, 16, 2007, 3:16 AM

Katherine Heigl at The 33rd Annual People's Choice Awards. Gregg DeGuire/WireImage.com - Wednesday, January, 10, 2007, 8:10 PM

Katherine Heigl at The 33rd Annual People's Choice Awards.Gregg DeGuire/WireImage.com - Wednesday, January, 10, 2007, 8:10 PM

Katherine Heigl at the 12th Annual Screen Actors Guild Awards. Albert L. Ortega/WireImage.com - Monday, October, 23, 2006, 6:23 PM

Katherine Heigl at the 58th Annual Primetime Emmy Awards.Steve Granitz/WireImage.com - Monday, October, 23, 2006, 6:23 PM

Katherine Heigl at the TAO Las Vegas First Anniversary Weekend - Janet Jackson Album Release Party. Denise Truscello/WireImage.com - Monday, October, 23, 2006, 6:23 PM