Times publisher Arthur Sulzberger Jr. hasn't had the easiest year: the paper's revenues are declining, hedge funds have taken hold of two seats on the Times Co. board, and he moved out of his Central Park West apartment when he split up with his wife of more than 20 years. Hopefully he'll be in a better mood today when Bill Keller wheels in a giant birthday cake to celebrate Sulzberger's 57th birthday. Others celebrating today: Art work fixture (and Studio Museum chief curator) Thelma Golden is 43. NBA commissioner David Stern is 66. Shubert Organization chairman Gerald Schoenfeld is 84. Bonnie Hunt is 44. Italian opera singer Andrea Bocelli is 50. Retired Rangers star Mike Richter is turning 42. And Scott Baio is 47 years old.