Pregnant Kate Middleton Leaves Hospital

This week was all about Kate, as it was announced that the Duke and Duchess of Cambridge, Prince William and Kate Middleton, are expecting a baby! Other big news this week included 2013's Grammy nominees being announced and the Obamas hosting the annual national Christmas tree lighting at the White House. See all the holiday prep and other events going on around the world — including an attempt at the skinny-dipping record! — in our week in pictures.