(press release) Nickelodeon's Eighth Annual Worldwide Day of Play to Combine With First Lady Michelle Obama's "Let's Move" Campaign and The President's Council on Fitness, Sports and Nutrition in Its Biggest Celebration of Play Ever, Live From Washington, D.C.'s Ellipse Saturday, September 24 First Lady Featured in Exclusive Event PSA Debuting on Sept. 3 NEW YORK, Sept. 1, 2011 /PRNewswire via COMTEX/ -- Nickelodeon is joining with the First Lady's "Let's Move" campaign and the President's Council on Fitness, Sports and Nutrition to bring for the first time its flagship Worldwide Day of Play (WWDOP) event to the Ellipse in...