Peach was referred to as "Princess Toadstoool." Bowser was "Bowser, King of the Koopas." They showed pictures of all the enemies and items, but they were just enlarged sprites from the game. There was a small bit of artwork that was rather mediocre.
Hmm, anyone have the manual(s) for the Japanese SMB1, 2, or 3? I'd love to see those. :)