Personally I think this a big mistake on Apple's mistake. There is nothing wrong with the current graphical environment in the i0S. It works and it's familiar why do they want to go down a flat button/Microsoft route for? I would think for Io7 they could open it up so that themes can be applied and reset the screen so that widgets can be added.
All of those things require filesystem access, they will never agree to it unless they put the themes in themselves and put in a control that allows you to select from a pre installed theme.
Apples motivation for releasing new IOS's is not what it looks like, but does it BLOCK Jailbreaking. The mistake Apple made was removing Personal Choice from the decision of which iOS you can use, our only choice is to NOT update to their latest iOS.
You'll notice there were 6 rapid iOS updates in a row when iOS 6.0 to 6.1.2 were jailbroken - the they gave bogus reasons for these hurried updates. The reason why they released 6.1.3 was BOGUS, it was released to break eVasi0n, not to fix the lock screen bug, because that bug was proved to not be fixed at all in 6.1.3.
So, if they do decide to make iOS look as flat and lame as Windows 8 tiles, I'll stick with iOS 6.1.2 and lock it down so it cannot be updated.
It's my personal choice to run Windows XP, Vista, 7 or 8, and I'm glad Microsoft does not force ut to use Windows 8.