I generally read up on any major iOS updates and maybe even wait a few days to see if any problems arise (i.e. phones being 'bricked') but decided to just jump into the deep end on iOS5. I updated both my iPhone 3Gs and original iPad last night. For the most part the updates went smoothly but there are a few caveats you might want to know about.
When you update to iOS5, iTunes will completely back up your device, clear it, install the new base code, then restore your media files (music, movies, photos, etc.) but it does not restore your apps. Before you go into panic mode it is very easy to overcome this. Go to the device summary in iTunes and select Apps at the top. Make a minor change (move an app to a different page, uninstall an app, etc.) and click Apply. iTunes will faithfully replace all of your apps and folders just like they were before the update with the exception of whatever change you made to get it to allow the sync.
At some point, possibly at the 4.3.whatever update, iTunes decided I no longer needed to sync my apps. I only noticed this change recently and had been intending to correct it but didn't want to lose some of my saved data that iTunes sternly warned me I would lose if I should enable this function. In my ignorance I did not enable App Sync prior to updating my iPhone and, therefore, it later showed only the default apps and folders that happened to contain default apps from my previous customizations in the greyed-out graphic. I was able to enable and apply the app sync and get all of my apps pushed back to the phone... in random order... without the benefit of folders. I've been spending my time between calls today getting things back in order.
Now, about the update itself.
My absolute, hands down, no discussion favorite new feature is the ability to select alert tones. I suppose you could call this more of an unlocked feature that has been present on every other smart phone before or since the iPhone was introduced four years ago but I'm still thrilled they enabled it. You can also see your ringtones as an option but they likely won't work (read on). Through a little research I learned how to make custom tones. It's the same process as creating a ringtone but it has to be less than 15 seconds long.
There are several other updates that you can read about in detail on other sites but I'm going to highlight some of the ones I like. The notifications screen is cool (swipe down on a home screen to see it) and it's nice that you can now flag mail but these aren't barn burners.
I have had a couple of Microsoft Zune devices and they've had WiFi sync since day one. Given that the iPhone, iPad and iPod touch have had WiFi since their respective introductions it's nice to see this come to iOS. It's a very handy feature.
iMessage is a nice way to stick it to the evil empire of your service provider. It allows you to send an SMS directly to another iOS5 device. If you have unlimited texting I suppose this doesn't really matter.
iCloud is a nice comfort. It can store your music, photos, documents, contacts and, if you want, device backups. It will be nice to sync contacts and documents between devices. With iCloud you get 5GB on a free account. The cool thing about that is your purchased music, apps, books, and TV shows, as well as your Photo Stream, don’t count against your free storage.
Photo Stream is an iCloud feature that I have decided to turn off. Every new picture you take is automatically uploaded to your iCloud for 30 days up to a maximum of 1,000 pictures. It allows you to sync photos seemlesly between iOS devices.
At first blush this seems really good but consider this: It's all or nothing. Every. Single. Picture. you take ends up in the photo stream. It doesn't matter if you're grabbing a Kodak moment or sexting, it gets pushed to the cloud. I have found no way to delete photos. If you turn photo stream off it will delete all of the photo stream photos from your device but they're still in the cloud (for 30 days, at least). I have also found no way to send photos to the stream from the camera roll nor have I found a way to view (AKA share) photos via the web or other means. Nope, not mature enough and has too many holes in it. It stays off.
There are a couple of features missing from the 3Gs but not much. Safari is supposed to have tabbed browsing now but they aren't present on the 3Gs. There is also simple photo editing in the camera app that is supposedly missing but I saw it in the PhotoStream and Camera roll.
Here are a few things I noticed about some of the new features that are not necessarily clear.
WiFi sync has to be turned on in iTunes. I was wondering why it wouldn't work last night and found the setting this morning. Plug in your device then highlight it on the left side of the iTunes window. Near the bottom of the summary tab you will see a selection that reads ‘Sync over Wi-Fi connection.' Check it and you should be good to go (haven't had a chance to test it, though).
I noticed another setting this morning that I haven't had a chance to investigate. It looks like you can sync (maybe it was backup?) to iCloud *OR* to the local computer but not both. I'll update once I get more info.
The new reminders function/app is supposed to have location-based capabilities. That ability does not seem to be present on my 3Gs. I'll have to look deeper into that as well.
It appears that the NewsStand cannot be placed in a folder. I have tried and the folder keeps running away no matter how hard I try.
NOTE: I was going to try out iMessage and my contacts were GONE!! Luckily I located a fix at http://www.seangw.com/wordpress/index.php/2011/10/ios-5-upgrade-lost-my-contacts/
That's my experience so far. I'll let you know if I run into anything else worthy of note.
Oh, one more thing (yeah, kinda on purpose). Before you update, be sure you backup your device and transfer purchases... just in case.