After I posted my thoughts on flat design I checked a couple of my regular sites and saw that 9to5mac.com has a new post up called What iOS 7 looks like. They had someone in their graphics department mock up what the new icons look like. Say it isn't so...Here is an except from the post regarding the icons.
Yes, they are flat. Our in-house Photoshop guru Michael Steeber has mocked up (Above) the icons based on descriptions which closely match what I believe we’ll see tomorrow.