Young professionals are flooding cities, determined to make it (you know, in that "Mary Richards circa 1970" kinda way). Now they have a road-map -- and with it, more competition. From retail giants to universities to financial firms, Forbes has compiled the top employers hiring in major American cities according to the results of SimplyHired's employment outlook. Top employers in New York? Barnabas Health, Citigroup, JPMorgan Chase, AIG, and GAP. The bulk of those make sense for the financial capital of the world. As for the fifth choice... Joey Tribbiani said it best.