Why iOS 7's design is bold but flawed

The final major problem I see is with the general lack of emphasis and differentiation between choices. Action sheets in particular feel too austere to me in their current form; with button borders gone and the only indication of the “preferred” choice being ever-so-slightly bolder text, I worry about user confusion. It’s impossible to tell at a glance what the least destructive option is, and sometimes it’s hard to tell what’s content and what’s UI.

Well written analysis.