So, I thought this was really good. I think it recontextualizes Event Leviathan and may even bookend the event itself? Like is the Event: Leviathan miniseries set in the single night after Lois rings the alarm on Clark being kidnapped? It seems that way, though it would not be out of character for Bendis ot have a giant all hands on deck rescue mission of the JLA occur entirely off panel.
Anyways, I liked the Loene and Leviathan meeting. Though Bendis propping up his new characters with other new characters was kinda eye rolling. I liked that it touched on the Invisible Mafia again though.
The Lois chapter was excellent and I'm now really officially excited about Rucka's book. That was a great showcase for Lois Lane and I liked everything I saw there. Even the emergency smokes. Very human Lois, said a lot about her relationship with Clark even though they don't share any panel time in that chapter.
The Jimmy Olsen chapter was also excellent. It really is like Fraction's Hawkeye on steroids or acid. Teases some multiversal hijinks and hopefully Dex Star as a sidekick.
And the Clark chapters were similarly well done. Really kept the tone of Action Comics. Nice to see some journalism from Clark.
As for hints to Leviathan's ID? I don't know of if I caught that many. They may know that Clark was Superman. From their talk with Leone and their reaction to Talia's actions it seems like kidnapping Clark wasn't Leviathan's plan.