So I decided to try Wild Cards a few weeks ago. I'm currently in the third book, I suppose because I found the series sufficiently gripping. I thought about sharing my experience with the series here, because I didn't want to hijack someone else's thread to do it.
I'll post short reviews (no spoilers) of the books as I get to them.
Wild Cards I:
Honestly, I liked most of the stories in here, especially the earlier chapters describing the first 20 years of life after the virus. Waldrop, Zelazny, Williams, and especially Martin and Snodgrass all wrote some generally thoughtful and stirring pieces which form the foundation of the whole series going forward. The story keeps returning over the decades to centerpieces from these stories such as Dr. Tachyon, Croyd Crenson, the so-called "Four Aces", and others. Even certain places like the steadily growing district of Jokertown begin to feel like characters. As these early stories flow into one another, the series evolves emotionally. This part of the book gave me a huge Watchmen vibe (which is a very good thing), and events take a pleasantly dark turn as mysteries and conflicts crop up that obviously will span more than the one book (especially in the stories by Shiner and Leigh).
However, the later stories lost a lot of that luster in my opinion, with some of the other writers wielding heavy-handed styles that use a huge number of POVs in a short space (which is disorienting), or exhibiting overly gratuitous scenes of sex and violence beyond anything I remember even from ASOIAF. Both heroes and villains gradually get more cartoonish at this point. The last story (by Miller) before the epilogue is downright flat, robotic, and predictable.
By the way, I read the 2010 Tor Books reprint of the original novel, which added 3 new stories by new writers. The stories by Cassut and Vaughn were uninteresting and rushed... but the story by Levine was a real gem of political intrigue and unlikely heroism.
Ultimately, after the blunt shock value and inflated peripheral cast in the second half of the book, I was already reminiscing fondly of the first half of the book when Zelazny, Williams, Martin, and Snodgrass kept me reading late at night. More and more, I just wanted to return to Tachyon, who is by and far the most empathetic, active, and very ironically the most human protagonist of the story.
So overall, I definitely found myself moving onto Wild Cards II: Aces High the next day, hoping to read lots more about those central characters I mentioned earlier and grew surprisingly close to, characters like Tachyon, Croyd and the Turtle. In that respect, Aces High was quite satisfying, and spent more time on over-arching conflict and mystery. However I would end up disappointed that Aces High actually ramped up the disorienting style of using dozens of tertiary POVs (for sometimes as little half a page) to describe events that would have been better off left shrouded in some mystery... More to come.