9.3.5 => 10.0 is not a "security update".
Constant nagware until you update is asinine. "Update Now or Later?"... f* you, I don't like what I see in 10... but I'm stuck with dancing around daily fucking warnings.
I swear... I'm not bitter :) I also won't buy another iPhone.
On every single minor "security" update...
I'm of the "avoid popups at all cost" school of UI design. As soon as you let developers have modal UI that isn't meant to accomplish a specific, user-initiated task, they will immediately start using that power to be obnoxious.
Update: Still getting nuisance notifications.
Long story short, I'm pretty sure this phone is my last iPhone.