Better than Final Days, not improvement in characters, but in balance between investigative and action parts. Previous book had focus on more in action parts.
Things that tickled my imagination in Final Days was the Founder Network and i was curious the know more of them, which i did, but not enough, so please Mr. Gibson, i need one or more book heavy on Founders stuff. I got sucked in the plot, kept me guessing almost to end, just right amount of twist and turns.
World building was good and keeping mind that this is only 350 or so pages, that's something, you don't necessary need 1000 + pages like Peter F. Hamilton and hundreds of characters to make it work, though Hamilton is still master at epic-sci-fi.
Style of writing in sci-fi tends to be sometimes heavy on technobabble side and all those fancy future stuff overshadow story and characters, for example like in The Quantum Thief, not in Gibson writing, you get your tech stuff, but they serve the story.
There are some loose ends, like Inimicals and once again Founder Network get's only teasing, come on! I need my Founder trilogy or something! All the Lovecraftian glimpses of ancient aliens got me going so there is no excuse to not to tell more. Fine book, and i really need to read Shoal trilogy