Here's a new one on me; I found this bit of DC promotion in the pages of All-American Men of War #24 (August 1955). And yes, the special TV episode is on Google Video.
Update: That's actually a pretty terrific episode. Since we're on the topic of Superman doing good works, I thought I would mention Superman's extraordinary speech from the Christmas, 1945 episode of the radio show. The first time I heard it (about ten years ago) I was overwhelmed:
A lot of people don't know that this is what's meant by "truth, justice and the American Way"; the last part is often interpreted as some sort of slam at the Soviets (and indeed in the 1950s the phrase was often used to contrast the USA with the USSR). But in the Superman radio show it was a reference to America as the melting pot, and a plea to listeners to treat each other with dignity and respect, without regard to race, creed or color. The radio show went on to present many famed episodes in those early postwar years where Superman not only battled against crooks and conmen, but against merchants of hatred and intolerance, in stories like Clan of the Fiery Cross, or Knights of the White Carnation.
Update: The Beat Down also has a well-worth reading post on the TV Superman.
My first experience with Superman was via the TV show "Adventures of Superman". George Reeves introduced Superman to me and will always be indelibly inked on my brain as the definitive personification of the character.
That was my first experience with Superman as well, although I confess that over the years I've really come to appreciate how much we know of the Superman legend came from the radio show: Jimmy Olsen and Perry White, the Daily Planet and Kryptonite. "Up, up and away!" originated as a verbal cue to listeners that Superman was going to fly. And when Bud Collyer had to go on vacation, they often worked in a story or two featuring Batman and Robin. :)