As a professional graphic designer I was shocked by what I saw in both a good and bad way. My thoughts:
Function:
As far as functionality goes, I was delighted to see a control center (minus the design) and notification center updates as well as new multitasking. SOME of the new apps look like a step in the right direction (photos, calendar, settings, safari minus the icon). However simple things like not being able to quick reply to messages is baffling. Its in the new OS X but not here? Seems like a huge selling point.
Look:
However all of this has been hampered by thin "line drawing" style icons and "buttons" mixed with garish, child-like home screen icons and color choices. The home screen icons are literally all over the place in terms of design. Gradients have never been harsher and more in your face than they are in iOS 7. Not to mention most designers growl in the face of gradients that look like these. Game center has glossy bubbles while others have a completely flat appearance. And lets not mention the disaster that is the safari icon. Its just plain ugly and Apple will be forced to change based on just about every comment on the web- no matter how much one loves the new OS. A much more middle ground would have been preferred here as far as the icon design (a simpler gradient , no gloss ,iOS6 modification). They also need some sort of subtle shadow underneath to not blend into the wallpaper image as we currently see on many screenshots floating around. Helvetica Neue was a good choice for font so not much to say there. Maybe use light instead of ultralight in some place.
Bad apps:
Some of the apps are really beautiful like weather (taken from yahoo almost pixel for pixel) while others like camera are just plain ugly. The mix of actual graphical buttons and pure text buttons in the music and photos apps is a confusing mess. The now playing screen for music should not be white and draws attention away from the album art. Notes and reminders look like they still belong comfortably in iOS 6? Textures and inner shadow on the font? Hmm.
Hopefully they sort all this out in a few months but iOS 7 is quite jarring to be gushing over and looks very unfinished. And if those icons ARE finished, I bow and shake my head in disbelief.
Say what you will but in certain areas Forestall got a lot right (minus the green felt). The iOS 6 Music app style is a great example of a middle ground between flat and textured design and is a much better design example that they could have built upon.
I realize everyone will not agree but the thread is for pro graphic designers to sound off.