Apple has set fire to iOS. Everything’s in flux. Those with the least to lose have the most to gain, because this fall, hundreds of millions of people will start demanding apps for a platform with thousands of old, stale players and not many new, nimble alternatives. If you want to enter a category that’s crowded on iOS 6, and you’re one of the few that exclusively targets iOS 7, your app can look better, work better, and be faster and cheaper to develop than most competing apps.
See also what Mike Monteiro said to Om Malik:
It’s a breath of fresh air. Where was Apple going with the current crap? This opens up all manner of possibilities. I’m excited because it’s new. And fresh. The Forstall crap went to its logical conclusion. Any design system that can no longer be extended is death. The new stuff is a fresh start. Eventually it’ll die too. But right now I’m excited about how it can grow and be extended. It’s not perfect. But, as a designer, that excites me. As a consumer? I dunno.