I'm going to have to let Wonder Woman #601 settle in for a bit. It's very clearly a temporary thing now. The timeline is just plain wrong. The Amazons shouldn't be hiding. The bare-chested man with the lightning should not be in power. Aphrodite withdrew her protection for some unknown reason. Hippolyta should never have died. Diana needs to learn a lesson about mercy and forgiveness. We know from Wonder Woman #600 that someone--presumably the gods--intends to teach the world to appreciate Wonder Woman, so Aphrodite might not have been angry when she did it. On the other hand, there are those dreams of fire and Diana's old costume. Maybe Diana herself did something that set this off. Either way, this is seriously an Age of Apocalypse-style storyline.
The thing with Age of Apocalypse, though, was that you knew certain things about the characters were WRONG. Cyclops should not be working for Mr. Sinister. Havok's jealousy should not go that far. Jean should not be with Logan. Pietro's sister should not be dead, and he most certainly shouldn't be the calm one in the family. (Though man, I adored the AoA Pietro. Maybe they can have him show up and kick Ultimate Pietro's ass. Who knows what using time powers at the end of that universe could cause?) So, of course, by the end of the story many of these things worked out (Jean and Cyclops), and others led to a tragic destruction (Havok gets it easy in the normal continuity compared to his brother and girlfriend anyway), and other items seeped into the regular continuity because they found a way to fit them and capture a twinge or potential (Blink) or just some of that wrongness. (Dark Beast!)
I'm certain that the Amazons away from Themiscyra, and Hippolyta's death are WRONG and are the things that need to be rectified to get the old timeline back. The Lightning Man will also need to be defeated, but he'll seep into regular continuity somehow. Even if he's just a manifestation of Ares or Zeus and can't show up as a bad guy on his own, we'll see some echo of him in the future.
What worries me with this writer is Diana's bloodlust after the Oracle shows her mother's death. Rage would be a natural reaction, but we know that Diana at heart is a forgiving person, and she can't bring herself to murder in revenge. This was a theme of Simone's entire run, after all. This new Diana is set up so that you can see her attempting it. That's the Wrong part of our alternate Diana. Now, the ideal story of this sort of lost timeline thing has the hero attempt the Wrong Action, only to have an epiphany (it might be externally prompted or just something deep inside them) at the critical moment and finding the Right Action instead. From what I've seen of JMS using Superman as his moral issues mouthpiece? I'm not sure I trust him to realize what the Right Action is in the end. I'm worried he'll go for what he thinks makes Diana more formiddable or interesting and finagle some way to keep it past the righting of the timeline. But we'll see. I will say, having a Diana from this alternate timeline deal with the results of all of Vol 2 and 3 without remembering exactly what went on could be fun for a storyline or two, but it's not really a good status quo for Wonder Woman.
I wasn't terribly impressed with this issue, and I was rather disappointed not to get a glimpse of the gods and what they are up to (I've been incredibly disappointed for years not to see Hermes in action again, but I'm pleased that Aphrodite is the goddess who brought this about--she's been HORRIBLY underused since CoIE. I suspect an inability to deal with Trickster good guys, because Aphrodite is arguably a Trickster figure too. TY NF Houck for this insight), but it wasn't soulsearingly awful. It wasn't even Byrne awful. The pacing just seems rather slow, and his Diana doesn't really interest me yet. She seems weak, and ineffective, and even though she's driving much of the plot with her actions she seems like a pawn being battered about by the Fates. Hippolyta seemed a hundred times more impressive in death than Diana does in this entire issue. Things can change, though.
The overarcing mystery of just what caused this is still intriguing, the plot itself is not the worst thing I've said, and there's the promise of our old Diana back soon. The problems of the pacing and Wonder Woman herself being less of a wonder will be difficult to overcome. She's more flat and boring here than she has ever seemed to me, and I started collecting her series back during the much-maligned Byrne days. Hopefully the point is to bring her into herself, but she's still supposed to be able to grab you from early on. The only reason I'm reading the next issue is that I know Diana from before and want to see what happened to change everything. That's not exactly a good recipe for new readers.