Now that the cover of the 2011 Sports Illustrated Swimsuit Edition is no longer a secret--thanks to an office worker who leaked it on Twitter Monday afternoon, followed by an anticlimactic David Letterman reveal at midnight --it's time to turn our attention to the contents of this iconic annual issue.

Let's begin with model Kate Upton , age 18. According to the Sports Illustrated website, Kate Upton "is a Midwest native who always dreamed of being a model. Fantasy became reality three years ago when she walked into an open call and booked her first job. Since then she has been the face for Guess Lingerie and appeared on the cover of Cosmopolitan Bride. This is Kate's first appearance in the Sports Illustrated Swimsuit Issue." She also has a cool Cindy Crawford-like mole.

Here she is, shot in the Philippines by Raphael Mazzucco. The issue is on newsstands now.

Now back to our cover girl, Irina Shayk . The 25-year-old burst into tears when she found out she made the cover on David Letterman Monday . When Matt Lauer asked about her relationship with soccer star Cristiano Ronaldo, Shayk, who was born Irina Shaykhlislamova, said "We Russian, we keep secrets."

Here she is, also shot in the Philippines.

(Credit: Raphael Mazzucco/Sports Illustrated)

And here's that cover again.

(Bjorn Iooss/Sports Illustrated )