I just saw "Crimewave" the other night, and in the scene at the newsstand I noticed issues of "World's Finest," "Superman," "Action Comics," "Joe Palooka" and "Mutt & Jeff" on the stands.
Got me wondering if Clark and Superman are one-and-the-same in those comics. Does that mean that every kid in Metropolis knows his secret identity?
They're presumably the "true-crime" comics that the DC Comics of Earths-1 and -2 published about their world's native superheroes; a late 60's Batman story covers Batman dealing with his world's DC Comics. Thus, they'd probably be similar to our world's versions, but just not have anything about their secret identities (unless they made up a secret ID for Superman for Earth-1/Earth-2's Superman comics...).