Ok - here are my first impressions:
Cons:
- New color scheme and flat look is awful. Looks like it was designed by a sixth grader whose parents are still living in the 80's. I suspect that iOS 7.1.1 will remedy this with a 'classic theme' option.
- New picture organization makes little sense.
- Better location services and the ability of the phone to keep track of your favorite locations means lower battery life (unless you micro-manage the settings like I do.

)
Pros:
- Control-center. 'Bout time.
- Finally, you can put more than 8 apps into a folder with the 'scrolling within the folder feature'
- The new way to close apps running in the background is good - no need to hover over an app and wait for the little red x's.
- Safari is a bit better.
-Z-man.