I have an iPhone 5 and I downloaded iOS 7 earlier today.
Verdict? Meh. The visual overhaul strikes me as someone (Jony Ive) wanting to make his mark and purge the old skeumorphism, rather than being absolutely necessary. I'm not seeing too much beyond a drastic visual refresh as the iPhone 5 doesn't have the fingerprint sensor, so even that novelty is missing for me. When I finished the install while connected to iTunes, I was told I had to download a Podcast app from the App Store...since when did the iPhone on-board music player lose this capability?
The Android apeing continues. Remember when the Android-style notifications centre appeared? Well, now the Control Centre with its volume controls and radio buttons has arrived - I've still got my LG Optimus P500 I picked up in early 2011 for £150 running pretty much stock Android, and it has the same functionality. One thing it did have that iOS 7 doesn't is a button to turn the 3G on and off, incidentally.
Now, the new look itself. iOS may have looked stale and starting to show its age, but at least it was a unique and different look to the armies of competing Androids. This is no longer the case and I'm vaguely reminded of a re-skinned HTC Sense in some ways.
Unless I'm going mad, I'd say the overall volume coming out of the speakers has been reduced overall as well, irrespective of your audio settings. I left them the same as on iOS 6 and it's noticeably quieter one media playback, although not by desperate amounts.
The battery life is also suspect and definitely not as good, but others have also pointed this out so I don't feel like I'm going mad on that front. Idling at standby with the screen turned off, under iOS 7 the battery is dropping to 95% in the same length of time iOS 6 dropped to 98% under the same conditions - switch on WiFi or 3G while playing back some media and it plummets further.
Overall it's "shiny shiny", but underneath the shiny veneer nasty things do lurk. It needs another coat of polish which I'm sure is coming in due course.