I don't. But I put iOS 7 on my old iPhone this morning. My iPhone 5 immediately looks radically different as soon as it's awake, and since you interface so visually with your iDevice (I upgraded an iPad 4 as well) it feels like you have a new product. The whole look of the interface is changed, and some will find it jarring, but it's surprising how soon you get used to it, and how quickly the old interface looks all clunky and wrong (like on my iPad 1).
The home screen can now have a moving background, and the all-new Apple apps often show clever little touches. For example, the clock icon now tells the correct time with a sweeping seconds hand.
Largely, the whole redesign is effective and elegant. The Compass app has been redrawn to be neatly clearer - and swipe it to the left to get a level.
Siri, freshly (and finally) out of Beta, now also accesses Bing, Wikipedia and Twitter for information, adding more resources to a query.
And its new visual interface is lovely: first a thin line appears along the bottom of the screen. The line turns into a sound wave mimicking your voice pattern when you talk, to show Siri is listening, and when you stop speaking that line curls up around the Siri microphone icon and then spins to indicate it's seeking a response. It's a nice demonstration of Jony Ives' software design aesthetic at work (until recently Ives was just head hardware designer).
If you don't talk for a while, Siri plays the two-tone prompt and begins listing a number of things you can ask. This list was scrollable with a finger but now five hints show up at a time, then fly off the screen.
Siri works in eight languages with 19 regionalisations (ie, English with Australian, UK, Canadian and US accents, Spanish for Mexico, Spain and the US, and Chinese divided into Hong Kong Cantonese, mainland Mandarin and Taiwanese Mandarin).
For those with accessibility needs, Siri now controls more elements of the system - for example, while boarding a flight with your hands full you can now invoke Siri and say 'Turn on Airplane Mode'. This is partly because Voice Control is gone, with Siri taking over its functions in addition to the services it already provided.
There's lots more about the new Siri abilities on TUAW.
My personal favourite tip for Siri is that you can set your title for when it refers to you directly. Therefore, Siri announces things like 'Sorry, Sublime Being Three, I can't look for restaurants in New Zealand' ... which also points out one of its localisation limitations.
To do this, just activate Siri by holding down the home button and wait for the beep. Now say 'Call me (favourite epithet here)'. This can be your name or anything else.
Siri will reply 'From now on, I'll call you (your preferred epithet). OK?'
You need to confirm, so just reply 'OK'. Fun! I have also added titles for other people, so I tell Siri "Call My Great Dad".
iMore has more on Siri customisations, for example adding phonetisised spellings so it says names more correctly.
Generally speaking, apart from the excellent new Control Center (sic) that appears when you swipe upwards from the bottom of the screen, giving you instant access to settings you access often including a flashlight.
There's quite a lot about Control Center on TUAW.
Folders now have greater capacity. Up to iOS 6, you could place 16 apps in a folder. OS 7 lets you have nine apps per page, and 14 pages per folder for 126 apps total.
A little blue dot next to an app name means an app has never been opened, as a handy reminder you have yet to try an app you have downloaded.
Some changes take a bit more of a mind-shift. In iOS 6, to switch apps you double-tapped the home button to access a list of recently-running apps, which appeared as a horizontal list along the bottom of the display. iOS 7 provides a tableau of screen shots enabling you to select an app with a single tap.
Quitting apps was always a contentious issue in iOS. Everything you ever opened carried on running, whether you restarted the device or not. Hardly anyone, in my experience, knew how to properly quit them to save RAM and some CPU cycles, not to mention (in some cases) data transmission to and from, for example with the Facebook app, you didn't necessarily bargain for, which could use both battery life and data. Up to iOS 6 you had double-click the Home button, then hold your finger on an app in the Application switcher along the bottom until it stated to wiggle (Edit Mode), then click the minus sign on the wiggling icons to quit them. In iOS 7, you just push any app's screenshot upwards from the tableau - much easier, and I do hope it's one thing every user learns, as I found one guy whose iPad only ran for two hours on a charge and it turned out he had nearly 300 apps running!
AirDrop finally makes swapping files between devices easier. It's available from Control Center. It can only swap files between people on you contacts list, but you can quickly change it to Everyone by tapping on AirDrop in Control Center for those work meetings - as long as they all do that as well. Then activated files (Notes, Contacts can send a business card to other users, Voice Memos, Photos which AirDrop lets you preview before accepting), Safari, Passbook, Maps and Podcasts, so far, and developers will hopefully add the capablities into their apps, too can be fired at anyone else on the same wireless network, once the Accept the transmission. Once the new Mac OS comes out, Macs will be able to send and receive to iDevices and vice versa the same way, saving lots of clunky workarounds we've been employing up till now.
Now, I can hardly wait for Mavericks (Mac OS 10.9).
[There is plenty more about Apple's new and free iDevice Operating System online, and I link to many handy sites on my www.mac-nz.com site under iDevice.]