The 19th Annual Essence Festival is set to take place in New Orleans July 4-7, 2013 and organizers have announced that Beyoncé will headline the main stage one of the three nights.  She joins previously announced performers Maxwell, Jill Scott, Charlie Wilson, Brandy and LL Cool J, among others.  Beyoncé won her 17th GRAMMY Award on Sunday (February 10) in the Best Traditional R&B Performance category for her hit "Love On Top."  She's currently working on her fifth studio album due out later this year.  The mega-star tells Vogue that the new project "is a lot more sensual... empowering" and the material celebrates being a wife to Jay-Z and a mother to Blue Ivy.  Beyoncé will kick off her "Mrs. Carter Show" World Tour in Europe on April 15 in Belgrade, Serbia.