iOS 7 is a big departure. But while doing this apple has managed to confuse some of us a bit. There are of course many mind blowing changes - like the one for the Photos app (renamed cutely as "Moments"). Or the Weather app - it literally killed my favourite weather app from Yahoo . The new Music app is perhaps the best app for music - even better than my favourite Ecoute. iTunes radio is also well designed.
Then what's my issue? My thing starts with the Home screen itself. There are two extremes there in terms of look and feel. While calendar or clock looks simple there is extreme textures in use in the case of Passbook or Store icons. Reminders and notes look odd too - they all look totally contrasting. Some of the colour choices are confusing - while I am not expecting to see pure black and white in use, considering how minimal are the options for customisation they had to strike a balance. This is what was playing in my mind while I was listening to the keynote last night. The control centre looked a lot like Windows phone to give another example.
I understand it was almost like this we felt when the iOS came out first. It will definitely go through many iterations in next few years before it settles for a permanent look. But iOS rarely changed its standard set of icons in all these years.
Otherwise iOS is something only Apple can visualise and execute. The design shift is quite visible and detailed. They have gone for an all-flat approach that works brilliantly in most of the cases. I am waiting for my first hands on experience at the moment - it could change my opinion .