There is clearly a major issue with iOS 8.
My 4s is behaving very badly since I upgraded. The battery life is an issue, it keeps crashing, calls are dropping out and I can't even change the ring tones, which are stuck on default. The kids 5's aren't much better and neither is the iPad. Definitely worse on the 4. Bear in mind each type of device has its own download and I've repeated them, reinstalled, recovered etc with no joy.
I'veworked in IT for decades and have been responsible for complex software that is just a mission critical as ios8 is to apple and if I'd let something like this into the market I'd be unemployed. Maybe it's a design problem but the in depth guidance on how to reduce battery drain is in itself proof something is wrong. You shouldn't have to start reconfiguring your phone to make it fit for purpose. Sure tweaks to maximise things to fit your usage profile are fine, but to make is usable... Nope, not good enough. I'm a big, big Apple fan and have devices coming out of my ears for me and the family, so please don't force me down the Android route. Admit the problems and get a decent fix release out there even if you need 2 or 3 interim patches. I'm disappointed not so much in the issues but the response.
I had planned on buying two new phones and two new iPads when the new ones are released but that is definitely on hold right now.