Apple has distributed a list of security fixes in the just-released iOS 7 software update. And it’s as long and encompassing as you’d imagine any major platform update would be. I haven’t seen them online yet, so I’m reproducing it here for anyone who’s urgently interested. When/if Apple posts it to their knowledge base, we’ll update and link out.
I haven’t updated any of my devices yet, and I doubt I’ll go down the iPhone 5* path. I’m happy Apple addressed security issues. I hope they’ll backport some of these for devices that can’t run iOS7.