It's obvious that bases of the stories are similar, and the similarities don't end there. Both Superman and Batman leave someone they love behind on Earth; Clark Kent left Lois Lane behind after being recently married, while Selina Kyle is waiting for Bruce Wayne, her fiancé, to return. As their time away from Earth increases, the bond between the respective men and Wonder Woman deepens.
In Action Comics, we see the toll that his time away from Lois has on Superman. He grows tired and lonely, yet he fights on. During his adventure, Batman, ever the stoic figure, may not visibly showcase his loneliness, but his increasing brutality, fueled by a boiling anger that he tries his damnedest to keep at bay, is all the evidence we need to recognize that his time away from Selina is affecting him.
But where the two issues take drastic turns is in the depiction of their respective leading women. In Action Comics, Lois Lane is rarely seen as something more than Superman's wife. For this story, at least, she is the love interest, a character defined by her marriage to Superman. However, the depiction of Catwoman is where Batman #39 shines brightest. Selina is a much different beast than that Lois, with King and Jones depicting someone who stands on her own two feet outside of her relationship. Yes, there is worry in her voice, and in her eyes. There is a contained concern when she learns that time is a different concept in the desert realm of demons. But not once is her character lessened for it.
Selina stands by the choices she has made, and that her husband-to-be has made, and she doesn't need to explain herself to anyone. The relationships between Batman and Catwoman, and Superman and Lois Lane have always been different, and this issue, combined with Action Comics #761, highlights that fact. The timing is almost a blessing in disguise, considering that only a few weeks ago, King focused on the differences between the two couples by having them go on a quiet double-date. Now, once again, we see the contrast between the two, as well as an evolution of society as a whole.
Sure, Batman and Action Comics are separeted by time itself. Today's female characters are differently depicted than the way they once were, and perhaps this is one of the reasons why Selina Kyle allows the most recent issue of Batman to stand as strongly as it does. The basic premise of the two issues might be similar, but King's voice, combined with Jones' stellar artwork, make this issue of Batman a much more powerful entry, not only in the ever-deepening connection between Bruce Wayne and Selina Kyle, but in comics as a whole.