From the experts:
Truman is an upstanding presidential name that radiates an aura of integrity and moral truth, values any parent would want for a child. It seems definitely headed for a revival.
Also associated with writer Truman Capote, Truman was at the height of its popularity in the early twentieth century, around the time Capote was born. It reached its highest point—Number 249—in 1945, the year Harry Truman succeeded FDR.
Tom Hanks and Rita Wilson chose it for their son, and it's also the name of Martha Stewart's young grandson.
Truman Burbank was the ingenuous character played by Jim Carrey in The Truman Show, and Truman was the surname of Will in Will and Grace.