Tremendous advancement? What, new visuals and worse performance under the hood?
Name me one thing that iOS7 does better than iOS6 apart from the 'fresh new look', just one thing that people use every day. Don't tell me the crappy and cheap looking control centre either. I use that maybe once a week and even then I would be quite happy to dive into settings.
Let me count the ways
Previews in multitasking making it much easier to check and compare info between open apps without having to actually switch in and out of the apps in question.
Not needing an ad-laden third party app just to use the flashlight and yes, the rest of the excellent control centre which I rely on daily.
Background refresh.
The way that just changing the wallpaper also changes the look of so much else (the dock, the keypad, folders, etc etc).
Being able to slide anywhere on the screen to unlock, and not worry about missing the track at the bottom.
The much, much more solid wifi performance on my iPhone 5 (which was previously very flaky on IOS 6).
The fact that the music app now remembers what song I was listening to after IOS 6 introduced the maddening bug where playlists (including shuffle all music would frequently skip back several songs and repeat the same ones over and over.
The battery life. Controversial I know, but in all seriousness the best Ive ever had from my iPhone in five years of IOS use.
Swiping left and right in Safari and elsewhere.
All the photostream improvements, which my family and I use all the time shared posting to a single stream, video support, the activity stream that lets you see all the new pics and comments in one place..
Appstore auto-updating massive improvement.
Being able to swipe down from any homescreen for Spotlight (one gesture vs button pushing and swiping).
Multiple pages in folders no more Games 1, Games 2 etc.
I really could go on and on. Dont kid yourself IOS 6 has nothing on this OS as far as Im concerned.