Well, it's about time.
Golden and Silver Age Superman was a pretty lonely guy, with no one who knew his secret and no one to confide in. Although the Golden Age Superman was too manly too discuss it out loud. Or care, really.
|Pictured: FREEZE BREATH|
It's the reason that whenever you think of a DC hero pondering his situation via thought-balloon, you almost invariably are thinking of Superman. Batman talked to Robin and Alfred and that old police guy with the mustache. Wonder Woman talked to Etta and the Holliday Girls and her mother and the Amazons and, well, Wonder Woman never shut up, basically.
|About bondage, mostly|
Superman had no one to talk to, so readers were shown his inner monologue a lot.
This contributed, by the way, to his tendency more than his colleagues to break the fourth wall; with no one to talk to, he talked to us.
|"Instead, send that money to the Superman Super-Fan Club, to fund our campaign to put my face on the quarter!"|
You seldom caught Batman talking to the reader.
|Except in a Superman story. P.S. Superwoman's a dick.|
In case you never thought about it, it's also one of the reasons the Batman/Superman friendship was so important in the Silver Age; Batman was the only person Superman had to talk to (because who wants to talk to Supergirl?)
|Hey, Rob; ixnay on the Upermansay, okay?|
One of the most important changes John Byrne made for DC when they rebooted Superman after the Crisis was to have his parents still be alive. Many of today's readers were raised with the idea of the Kents as living touchstones of Superman's humanity and morality. But since Superman's re-reboot in the Latest Crisis, his parents have been dead; they died in a car crash, a solid reminder to readers that Superman can't be everywhere and fix all problems (and that not all problems are caused by supervillains or long-dormant diseases embedded in buried pirate treasure).
|Venal, greedy Martha! Killed by your own dreams of avarice, just like in some "Twilight Zone" episode.|
You had it coming, lady.
In the Silver Age, Jimmy Olsen was Superman's Pal-- Superman who lied to him every day of his life. And for no reason, really. The stated reason that Superman never confined to anyone who he was is that doing so might endanger their lives. C'mon, Jimmy's life was already in constant danger from being Superman's Pal. How could anyone's life be MORE in danger than Jimmy Olsen's?!
|Never a dull moment, eh, Lucy?|
No one has known quite what to do with Jimmy Olsen since Crisis. Heck, it's easy to make a case that no one knew what to do with Jimmy Olsen BEFORE the Crisis; that's why he was always being made to swallow noxious foreign substances with bizarre results. Like Jack Kirby.
Clark's reveal to Jimmy takes two problems and turns them into one solution. It gives Clark someone to relate to as BOTH Clark and Superman who knows his secret, and gives Jimmy and actual narrative function in Superman fiction.