After much anticipation, the first public release of iOS 7 was rolled out to iPhones, iPads and iPod Touches today. After a little perhaps unsurprising overloading of Apple's servers during the day (I received reports of people being told it would take 12-24 hours to download!), things appear to have smoothed out.
A notable number of updates to apps in the App Store over the last few days have included compatibility fixes as publishers stepped up for the imminent iOS 7 release. Developers have, as usual, had access to beta versions of iOS 7 over the last couple of months in order to root out and resolve any such issues. On the surface, Apple in the meantime appear to have ironed out instability issues that were present in the initial beta releases.
From this point of view, I don't have too many fears that the iOS 7 release will cause too many issues, and don't share other commentators' views that users should be too anxious about upgrading.
One aspect that will be interesting to watch is how flawlessly iOS 7 behaves on the iPhone 5S, Apple's new 64 bit device, given that public beta testing has been on 32 bit devices.